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Kanji Name ウルカヌス
Romaji Name Urukanusu
Title Goddess
Gender Female
Status Alive
Equipments Luna
Aliases Luna
Family Jupiter Sisters
Possessor Tsukiyo Kujyō
Seiyū Yuka Iguchi
Manga Debut Chapter 131
Anime Debut Doll Roll Hall (Episode)

Vulcan (ウルカヌス, Urukanusu) is the eldest of the Jupiter Sisters and is the third goddess revealed. She currently resides within Tsukiyo Kujyō.

Character Overview


When Vulcan is in control of Tsukiyo's body, Tsukiyo's hair and eyes acquire a crimson-red color. Like the other goddesses, Vulcan also has a halo and a pair of wings behind her back.


Despite her disabilities — feeble eyesight and poor hearing — Vulcan is very powerful. According to her, she breathes souls into inanimate objects so that they can act as her eyes, ears, hands, etc. She also reveals that she is able to use telekinesis, considering what she does to the objects in the library in order to attack Keima. Vulcan can only control inorganic objects, however, and seeing as she is unable to walk, she uses Luna as her "body".

Contrary to her inability to walk, Vulcan is still able to fly without difficulty.


Vulcan is a goddess who loves justice and delicacy. As such, she is willing to do anything to protect Tsukiyo, who she considers to be the embodiment of elegance.

Vulcan is a very charming lady. Towards the people she is fond of, like her sisters and Tsukiyo, she tends to speak with proper etiquette. She is fiercely protective of Tsukiyo, and sees Tsukiyo as a beautiful and pure girl. Conversely, she displays a rather aggressive behavior towards Keima and will not hesitate to punish him should he do anything that displeases Tsukiyo.

Additionally, because of Keima's disloyalty towards his conquest targets, his very being disgusts Vulcan. However, Vulcan has grudgingly accepted that Keima is desired by Tsukiyo, so she decides to aid Tsukiyo by telling (threatening) him that he should only be with Tsukiyo and no others.

In an omake, during some time spent with Tsukiyo, Vulcan shows that she becomes irritated when she is treated as an elder due to her poor eyesight and hearing.


Vulcan and her sisters are responsible for the past sealing of Old Hell. Their heroics unfortunately trapped them along with the Spirits, but were released when the seal is broken. At some point after the event, Vulcan enters Tsukiyo Kujyō, presumably along with Tsukiyo's runaway spirit. However, unlike the spirit, Vulcan had no immediate effect on Tsukiyo.

During the hunt for the goddesses, Vulcan begins to regain her powers through reasons related to Kanon's love confession. Vulcan displays some of her power by controlling Tsukiyo's doll, Luna. Being someone who strongly believes in justice, she decides to use Luna to punish Keima after seeing him with Shiori and for being unfaithful to Tsukiyo.

Character History

Old Conquest Arc

Vulcan's first appearance as Luna.

With Shiori's departure from the library, Keima is left alone. At this time, the room is gradually robbed of light and Keima finds himself suddenly being attacked by library objects. Unable to see his attacker, Keima tries to escape, but is unsuccessful. He eventually notices Tsukiyo's doll, Luna, floating in mid-air.

Luna, with concealed fury in her voice, tells Keima that he must not come near Tsukiyo. She eventually introduces herself as Vulcan - a goddess who loves justice and delicateness. She tells Keima that he must never come near Tsukiyo, because she is the most beautiful girl she has ever seen and does not want Keima to associate with her.

Keima shouts at Vulcan, asking what offense he has committed. Vulcan angrily responds that she saw him courting Shiori in the library, and as her anger escalates, so too does Keima's chance of escape, managing to deceive Vulcan with an irrelevant piece of paper. With Vulcan distracted, Keima takes the opportunity to flee. Vulcan tries to pursue, but Keima tells her that she should clean up and treasure the library. His tactic proves efficient, with Vulcan discontinuing her pursuit in favor of putting the library back in order. Shortly after, Vulcan finds Keima running towards Tsukiyo's location and tries to prevent him from doing so.

Keima, with a little assistance from Ms. Nikaido, eventually reaches the rooftop and sees that Tsukiyo has transformed into Vulcan. Vulcan says that she is a powerless goddess, but she can make objects move. She proudly states that she will protect Tsukiyo as long as she has her objects.

Vulcan then proceeds to assault Keima with a bench. As he hangs in midair, Keima angrily demands to talk to Tsukiyo. Hearing this, Tsukiyo emerges, and tells Keima that she feels the same way Vulcan does, since he never came to visit her again after her conquest. She declares her hatred for Keima and tells Luna (Vulcan) to drive Keima away.

With Keima's advances being prevented by Vulcan, he asks why he is being

Keima is condemned for his infidelity.

treated as an enemy. Vulcan responds with a deadly aura, saying that Keima was having an affair with both Kanon and Shiori.

Keima then asks if Tsukiyo does not trust him anymore, to which Vulcan responds with a very angry 'no'. Vulcan once again attempts to drive Keima away, but the persistent Keima tells her that he won't leave until he speaks with Tsukiyo. Upon hearing Keima's demand, Tsukiyo switches places with Vulcan, and tells Keima that she would have been happier if she was left alone. She then adds that she is ashamed for having loved such a terrible man. Keima replies that he had no choice. He then manages to bypass Vulcan's defenses and embrace Tsukiyo, saying that their encounter was destiny.

Tsukiyo blushes for a split second, then puts on an infuriated expression. She thrusts her fist into Keima's face with incredible force while Luna headbutts him from behind. After suffering physical punishment from the two, Keima tries kissing Tsukiyo. Witnessing his attempt, Vulcan uses her powers on Keima's clothing to pull him away from Tsukiyo. Keima, in his infinite genius, removes his clothing (an act that manages to shock Vulcan) and tries to attack Tsukiyo's lips a second time. Vulcan then hurls a barrage of floor tiles at Keima, severely draining him of strength. Vulcan announces her final warning to Keima: she will drop benches on his head if he does not go away.

Keima tells Vulcan that he will take any kind of punishment and implores Tsukiyo to love him back for a little while longer so that he can protect her. As Vulcan prepares for another attack, Tsukiyo intervenes, which causes a bench to drop onto Keima's head (since Vulcan's power is lost after the switch).

Caring for an unconscious Keima, Tsukiyo asks Luna (Vulcan) if they should talk about her sisters to him, but Vulcan firmly disapproves, and says that her existence should be kept secret from humans.. Ultimately, Keima's determination convinces Tsukiyo to aid him. Tsukiyo, with a bit of an effort, then pulls Keima closer to her. Subsequently, she gives Keima a kiss on the cheek, which causes wings to suddenly emerge from her back.

After the events with Tsukiyo and Vulcan, Keima returns

Vulcan and Diana are reunited.

to his house, only to be captured by Fiore who was anticipating his arrival. Minor events ensue, resulting in Vulcan's complete victory over Fiore after hearing Fiore's remarks about capturing and possibly killing the goddesses. While the previously mentioned events were happening, Diana approaches an immobile Vulcan in front of Keima's house. Noticing that her elder sister has grown wings, Diana wonders why her own wings have not emerged. With Fiore captured once more, everyone present proceeds to where Kanon slept. Along the way, Diana complains to Keima about not having her wings while Vulcan badgers him about supporting her physically.

As Vulcan inspects the enchanted knife stuck in Kanon's body, she realizes that the magic infused within the blade is merely an imitation, and notifies Diana that the two of them should be able to remove it without worry. They do so, but the knife's removal only served to save Kanon and Apollo from imminent danger. Following the discussion about Kanon's/Apollo's current status, Keima tells Vulcan to return home for the time being and protect Tsukiyo. He gives Tsukiyo a warning tag and tells her to be careful.

Few days later she, Mars, and Minerva were brought to Keima's house while their hosts were asleep in order to hear Apollo's oracle. Diana awakens her sisters and they had a brief reunion. Keima interrupted them and tells Diana to explain the current situation. After witnessing Keima and Elsie go back and forth, Vulcan witnesses Mars and Minerva get close to him, each claiming him for their respective hosts, Yui and Shiori. Vulcan (via Luna) grabbed Keima's head and held a pair of scissors to his left eye and wrathfully reprimanded him for tempting other women when he had Tsukiyo. Mars knocks Luna away and asked Vulcan not to harm him. As the three goddesses lay claim to Keima for their hosts, things in the room were being affected.

Diana tried to get their attention but they were busy trying to win Keima over. Vulcan, using Tsukiyo's body, leans against Keima and tries to entice him saying that he is lucky to have a girl like Tsukiyo. Mars does the same and showed off Yui's breast arousing the ire of Vulcan and complains that she was being unfair. Mars just replied that all's fair in war. Vulcan then began to throw objects at Mars hitting Keima as well but Mars just deflects everything. It continued until Minerva created a force field and pushed both of them away. Vulcan and Mars banged at the force field until Keima asked Diana to do something. Diana then tells them that Keima was Tenri's not helping the situation, they then witness Diana mumble. Keima then tells to go to the second floor and tells them off for their squabbling.

In Keima's room where Kanon/Apollo is and after Mars and Minerva asses how troublesome and tricky to remove the hydration spell is, Keima asked what are they going to do if they can't remove it. Vulcan replied that they will call her and have her remove it herself. Vulcan instructed her sisters to hold hands and with Minerva amplifying their powers, they called to Apollo. As they called to her, they outputted enormous power causing Diana to worry that the enemy might notice. Vulcan tells her that they can only call Apollo for a few second and would desist if she does not come out.

After a few seconds, they did not get a response from Apollo and Vulcan claims that it was no use, that Apollo has no intention of coming back and even though they gathered, their effort was fruitless. Keima then tells them that they should head back and he would take care of the rest. He tells them to be careful to not get uninvolved girls to be targeted. Vulcan agrees reasoning that they have no choice since he knows the precise information and appears to have no intention to share. She and the others who were brought over slept and let Elsie carry their hosts' bodies back to their respective homes.

Mai-High Festival Arc

Vulcan captured

At the time of the Mai-High festival, Vulcan - who has taken over Tsukiyo's body - is revealed to have been defeated by a Vintage member. She is then transported to the Vintage hideout along with a few of her sisters who have also been captured.

Much later, immediately following the events of Keima's reconquering of Ayumi and Mercury's subsequential emergence, Vulcan and her sisters are rescued by Diana, Mercury, and a large portion of the Runaway Spirit Squad. Afterwards, Vulcan and her sisters cast a spell that obliterates the entire Vintage hideout. Afterwards, the goddesses attend the Mai-High festival. Vulcan, Minerva, and Diana watch the performance of the 2-B Pencils (featuring Kanon) from the stage lights.

Heart of Jupiter Arc

Days after the festival, Vulcan and Mars can be seen talking at the rooftop where Tsukiyo usually resides. Noticing the miasma surrounding the school, Vulcan questions the party involved in the current situation. Mars (and at the same time Minerva, who is at the library) comes to the conclusion that the miasma is actually a spell used by the Weiss.

Vulcan and Mars notice the Miasma.

A short while after, Mars and Vulcan rendezvous with Minerva and Mercury. As Minerva leads them to the source of the miasma, Mars takes notice of Vulcan's increased weight. Vulcan blushes, and explains that Tsukiyo has been eating rather too well lately. She quickly dismisses the matter, however, and tells her sisters to be careful. Finally approaching the source of the miasma, the sisters hear a scream and realize that the cause is "Keima's devil-sister", Elsie.

After Elsie explains her predicament, the goddesses see that Keima is the source of the miasma. While they contemplated on the matter, Tenri arrives to disclose information about Keima's fate. When she finished explaining the situation involving Keima, she beseeches the goddesses to aid him in his journey. Vulcan then asks where the mentioned journey will take place, and Tenri replies, saying Keima will be going back to the past - more specifically to Maijima, ten years ago.

Vulcan contemplates the goddesses' fate.

Following Tenri's story, Vulcan wonders if those present at the time are all just part of some 'grand scheme' as she and her sisters construct and empower a magic circle to transport Keima back in time. At the spell's penultimate state, Mercury asks where/when they should send Keima. With the arrival of Haqua and Nora, Vulcan realizes that the "Key" has arrived as Nora brings forth the orb entrusted to her. After making final preparations, Keima and Elsie are transported to the past.

After the departure of Keima and Elsie, Diana calls for a gathering of the goddesses. She notes that the purpose of their conference is to establish a lover for Keima. As Vulcan frustratingly comments on Keima's seduction all of the goddess hosts, Apollo tells Vulcan that it's already too late for that since Vulcan has known about it for a long time. Vulcan's frustration escalates and says that she obviously cannot tell Tsukiyo about the matter. As Diana goes on to explain Keima's pre-meditated infidelity, Vulcan reveals that she would have ended Keima if Tsukiyo didn't desire him. She continues to insult Keima, saying that bad things will happen if they are to get involved with him and that it is in their best interests to simply forget about him. Upon hearing Vulcan's declaration, Apollo teasingly announces that Vulcan's host — Tsukiyo — has apparently relinquished her position to possess Keima. Vulcan blushes in frustration, and immediately objects to Apollo's announcement, saying that she never said that Tsukiyo has given up on Keima and that Keima's negative attributes are only common opinion.

Vulcan confirms the orb's activation.

Later, the goddesses notice a disturbance in space-time and come to the realization that Keima has failed. Vulcan concludes that their insurance — the Key/orb — has been put into effect, and Mars wonders if it will affect the present. Vulcan answers that one of the purposes of the orb must be to prevent any influence of Keima's actions to their own present time. Expressing worry, Apollo and Minerva both wonder if they should have told Keima more about the situation, but Vulcan says that according to Tenri, it is best not to reveal too much to Keima, even though they are aware of the dangers of his mission.

Afterwards, Mars announces that even though Keima's mind is somewhere else, his body is still present among them. She decides that they cannot simply let him stay there forever and so proposes that all the goddesses take part in a lottery, with the prize being Keima's protector. The winner of the lottery will take custody of Keima until he finishes his mission. Vulcan immediately disagrees, since Keima's hiding place for the time being is Tsukiyo's dwelling, and says that Tsukiyo will be able to protect him where he currently is.

Diana and Minerva decide to fight for Keima as well, with Diana saying that Tenri's

Vulcan gives details regarding Keima's plight.

house is warm and close in proximity to Keima's while Minerva argues that Shiori's house has a lot of books. In the end, the goddesses go along with Mars' idea of holding a lottery. The lottery begins, and in almost no time at all, Minerva announces that Vulcan loses. Crestfallen, Vulcan and Luna (with help from Vulcan) both hang their heads.

After the lottery, Vulcan reminded everyone that in order for Keima to return to the past, his seven year-old self had to be transferred to the present to take his place. Vulcan continues to sternly tell her sisters that should the now seven year-old Keima wake up, they need to render him unconscious in order to prevent any time distortions.

Sometime later, she talks to Tsukiyo and tells her to meet Keima surprising the latter. Being asked why, she replied that she had a terrible premonition that even though they agreed to watch over Keima's body without waking him but she isn't certain that Apollo and Mars won't do something mischievous and tells Tsukiyo to go and protect him. When Tsukiyo asked why she should, Vulcan just tells her that while she was protecting him that she should make him hers alone and to not lose, confusing Tsukiyo.

Sometime later, in the school library, when Tsukiyo, Shiori, Ayumi and Keima were attacked by a Mobile Colossus, she and her sisters took over their hosts to protect them. Vulcan notes that the enemy caught up with them and that Keima hadn't returned. When a car suddenly breaks into the library, the driver tells them not to fight it and to come in the car to guide them. After the Colossus wrecked the library some more, the goddesses and Keima got in the car and drove away. She and her sisters then returned control back to their hosts as they escaped.



No actual relation except for the fact that Vulcan uses Luna as an extension of her senses. Tsukiyo originally believed that Vulcan was Luna brought to life.

Tsukiyo Kujyō

With their mutual acceptance of Keima being a disgusting man, Vulcan and Tsukiyo form a meaningful friendship. Tsukiyo is Vulcan's good friend, and Vulcan wishes for Tsukiyo's happiness because of Tsukiyo's beauty and delicateness. The two treat each other with the utmost respect, as evidenced by their conversations.

Keima Katsuragi

Disgusted at the fact that Keima is involved with numerous relationships, Vulcan's primary feeling concerning Keima is something similar to utter disgust. Her loathing towards Keima is strong enough that she is willing to do almost anything to protect Tsukiyo from him. However, after Tsukiyo admits that she still has romantic feelings for Keima, Vulcan reluctantly decides to aid Tsukiyo in acquiring Keima's attention.

Jupiter Sisters

Being the eldest of the Jupiter sisters, Vulcan is highly admired by her younger siblings. Also, since she is the eldest, she tends to have a very slight commanding tone when addressing her sisters, though the tone is mostly ignored by her siblings aside from Diana and Minerva. Despite this, Vulcan makes sure to treat her sisters with respect.


  • The name "Vulcan" is derived from the Roman god Vulcan, the god of fire and smithing.
  • In Japanese her name is actually pronounced as "Vulcanus", which is the same as it is in Latin.
  • Vulcan claims in a conversation with Tsukiyo that her senses are not poor because of old age. However, given the fact that she is the eldest of her sisters and that she is also centuries old, it may not be too far from the truth.
  • In an omake, due to using Luna as a proxy a lot, her sisters sometimes talk to her instead of Vulcan even when she is in the same room.


  • (To Keima) "I cannot move... carry me" (Chapter 137, p.14)
  • (To Keima) "I do not understand...why a beautiful girl like Tsukiyo...would fall in love with such a filthy, creepy, suspicious man..." (Chapter 139, p.13)
  • (To Mars) "Mars! Don't use weapons that Tsukiyo doesn't have!" (Chapter 158, p.12)
  • (To her sisters) "If Tsukiyo didn't harbor feelings for that man, I would have killed him already. Nothing good can come from getting involved with that sort of man!! It's best to forget about him!!" (Chapter 190, p.4)