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Kanji Name マルス
Romaji Name Marusu
Gender Female
Age Unknown
Status Alive
Family Jupiter Sisters
Possessor Yui Goidō
Seiyū Ayahi Takagaki
Manga Debut Chapter 141
Anime Debut Punch DE Date

Mars (マルス, Marusu) is the second youngest of the Jupiter Sisters and is the fourth goddess revealed. She currently resides within Yui Goidō.

Character Overview


Mars has a rough, perpetually battle-ready personality that also borders on masculinity. She has a habit of using certain rude phrases that are not often heard from females. Being "a warrior who battles evil", she becomes very cautious when entering any unknown situations, as illustrated by her suggestion to Yui that she bring a weapon to her date with Keima, just to be safe. Due to her slight masculine nature — further promoted by her thirst for battle — Mars understands very little in the matters of romance. However, she has been shown to be quite flirtatious. Just like her sisters, Mars cares a great deal about her host, even going as far as taking control in times of danger. Although, because of her ignorance regarding romance, her attempts to make Keima love Yui are far from being romantic.


Mars' true appearance has not been revealed. Whenever she takes control of Yui, Yui's hair is held together in a single braid and acquires a blond color. A white head band also appears on her head and her eyes turn red. Similar to her sisters, she also has a halo on her head and a pair of wings at her back, completing the transformation.


Mars' strength has yet to be measured, but she is shown to be extremely powerful whenever she is in control of Yui. Mars is also a master fencer, and at one point (during Yui's date with Keima) wields a rapier to tear apart opponents' clothing without injuring them.

Background and Initial Appearance

A common similarity between the Jupiter Sisters is that they are the ones responsible for the sealing of Old Hell. None of them have shown their true appearance, and they all eventually ended up residing in a host along with a runaway spirit.

Mars' host evidently becomes Yui Goidō sometime after the release of Old Hell's seal. The ensuing regression of runaway spirits caused the goddesses to look for hosts in order to once again battle with the runaway spirits. However, unlike the runaway spirits, the goddesses had no immediate effect on their respective hosts and instead laid dormant within said hosts until the runaway spirit is driven out.

Character History

Old Conquest Arc

The Holy War...

Mars first appears before Yui after Yui's conversation with Keima (who was currently dressed as a girl). After their initial confusion, Mars introduces herself and wonders if her sudden appearance meant that the seal of Old Hell has been broken. Sensing that there might be danger ahead of them, Mars tells Yui to carry a weapon, but Yui is too preoccupied with thoughts of Keima to take her warning seriously. Mars then wonders why Yui is attracted to another man when she is a man herself, to which Yui responds by yelling that she is in actuality, a girl.

During the date, Mars' confusion regarding human genders escalates when Yui tells her that Keima is a guy, even though he is dressed like a girl. However, she is moved by Yui's determination (and her beautiful eyes) to a point that she convinces herself to assist Yui in fulfilling her love. One situation where she helps Yui is when Yui suddenly gains enhanced strength to repel the men who were accosting Keima at the time. She also helps protect Keima from the suspicious Vintage member (who is actually Haqua pretending to be one) using her toy sword. After the date, Keima relays information to Mars regarding the situation with the goddesses and Vintage. He warns her not to do anything rash since she and her sisters do not have the power they once did, and doing otherwise will only put herself and Yui in danger. Mars reluctantly accepts, and is given a warning tag which Keima tells her to cut should she feel anything that might put her in trouble.

Some time later, Diana asks Keima to gather the goddesses he's found so far. He asks for Elsie's help, and they bring Tsukiyo, Yui, and Shiori to Keima's room. Diana calls out to the goddesses in what is seemingly Heaven's language, and the goddesses simultaneously awaken. Mars is surprised, yet delighted to once again see her sisters, and they all share a tender reunion. She then notices Keima, and subsequently causes trouble — albeit unknowingly — when she tries to confirm Keima's relationship to Yui (that of her husband). She also mentions that she was opposed to their love, since Keima is an extremely dubious person, but claims that she decided to help Yui after understanding her sincerity. Witnessing the incredible revelation, the other goddesses immediately turn possessive/hostile toward Keima and decide to battle each other for him.

As the goddesses try to take turns in seducing Keima, Mars uses Yui's well-developed chest to her advantage, angering Vulcan, and then states that nothing is fair in war. The argument eventually ends when Diana intervenes, but instead of actually stopping them, she ends up getting angry at Keima and releases a dark aura which frightens her sisters.

Mai-High Festival Arc

At the night before the Mai-High Festival, Mars is revealed to have been severely wounded by Lune. She is then transported to the Vintage hideout along with her sisters — who have also been defeated and subsequently captured by Vintage members — and a few of Keima's conquest targets.

Diana, Mercury, and members of the Runaway Spirit Squad eventually rescue Mars along with the other captives, and together, the goddesses destroy the Vintage hideout using an unknown large-scale destruction spell.

Heart of Jupiter Arc

Vulcan and Mars conversing at the rooftop.

Five days following the events of the festival, Mars and Vulcan are found conversing at the rooftop of a school building. As they talk, they notice the miasma that has surrounded the school. Mars and Minerva (who is presently at the library) both realize that the miasma is a spell typically used by the Weiss. The point-of-view changes to Minerva, who figures out that the source of the miasma is the theater.

As Mars and Vulcan depart for the theater, they meet up with Minerva and Mercury. Mars, while carrying Vulcan, complains that Vulcan seems heavier than before. Vulcan tries to explain that Tsukiyo has merely been eating well lately. Unwilling to divulge more information regarding her weight gain, she masterfully avoids the topic by telling Mars and her other sisters to beware of the miasma ahead. As they reach the source of the miasma, the goddesses come upon Elsie and an unconscious Keima.

Seeing the goddesses, Elsie explains Keima's situation. Tenri appears moments later, apparently waiting for the goddesses the whole time. She then tells everyone present that Keima will be journeying back to Maijima, ten years past. Without a moment to spare, the goddesses then prepare an intricate spell that means to send Keima back in time. As they do so, Mercury constructs a barrier required for the teleportation spell. Mars tries to confirm Mercury's talent in such barriers, to which Mercury replies that even if it's her first time using a barrier on the type of teleportation they are about to achieve, it is still perfect.

Much later, the goddesses are seen to have arranged a sleepover at the Astronomy Club room. Diana reveals that the purpose of their gathering is so that they can discuss their future plan for Keima. As Apollo clarifies that the plan Diana refers to is about who among the goddess hosts will eventually be Keima's lover, Mars tries to avoid guilt by saying that she is only doing what Yui wants.

The goddesses then take turns in insulting Keima and his bad habits, and is interrupted by Apollo's mentioning that the important thing is how things will turn out in the end. Mars agrees, and says that all that matters is that Yui wins Keima. Her comment immediately sparks an argument, with Apollo bragging that no one can beat Kanon because of her status as an idol. Mars retaliates, proudly stating that Yui is the sort of girl that will ignore moral bounds and rape Keima if she needs to in order to convey her feelings.

Unwilling to get beaten without even trying, Minerva stutters that Shiori, as well, will participate in trying to acquire Keima. Hearing her soft declaration, Mars and Apollo simultaneously tease Minerva because of her childlike body; Apollo says that she can't hope to win Keima with her body, but Mars wonders if Keima is the type to be attracted to it. Having witnessed enough, Diana comes to Minerva's rescue, only to be a target for her sisters' berating. Mars scolds her for disregarding her host and falling in love with Keima, and Apollo tells her that her actions are worthy of shocking their ancestors. The argument continues and eventually wakes Mercury, but her awakening only served to further escalate the argument.

Time passes, and at another meeting, the goddesses notice a disturbance in spacetime. Mars notes that the disturbance must mean that Keima has failed in his task, and Vulcan confirms her observation by saying that the "insurance" — i.e., the orb — has taken effect. Mars then asks if its powers hold any influence in their dimension, and Vulcan replies that it does not because the orb seems to have been created for that very purpose. As the goddesses ponder more about their situation, they pensively gaze at Keima's unconscious body, awaiting his success.

The battle for Keima begins with Vulcan's loss.

Unable to do anything else, Mars decides to hold a lottery whereby the winner becomes Keima's protector while he remains unconscious. Various disagreements are then heard from the goddesses, which are ultimately ignored by Mars. She then begins the lottery and mentions that only those with a strong will shall win, even if the odds are equal between all of them. Vulcan was the first one out and the game eventually ends with Apollo being the winner for first and Mars being second.


Yui Goidō

Yui's relationship with Mars is similar to the relationships between the other goddesses and their respective hosts. They get along very well, even if Mars constantly mistakes Yui for a boy (if her constant mistake is deliberate or not isn't known). Mars will protect Yui from all danger not only because Yui is her host, but also because Yui is her dear friend.

Other Goddesses

The relationship between Mars and her sisters can be considered normal. They bicker and tease each other, but their love for each other is apparent.


  • Whenever Mars is in control of Yui's body, her hair acquires a blonde tint and is bound in a single braid. Additionally, a circlet rests upon her head.
  • The name "Mars" is derived from the Roman god Mars, the god of warfare.
  • Probably because the mythological Mars is the god of war, the Mars in the series tends to show a masculine personality. This may also be related to Yui's transformation from a girl to a boy.
  • Because of Yui's wearing of a boy's uniform, Mars is under the impression that in the human world, girls dress like boys and vice-versa.
  • Mars likes to gamble.
  • In the Volume 15 Omake, Mars still thinks that Yui is a boy, much to her host's distress.


  • (To Yui) "I really don't like this. I've got a bad feeling about it. Anyway, carry a weapon with you." (Chapter 142, p.4)
  • (To Haqua dressed as a Vintage member) "Disturbing my friend's date ... I, Mars, will not forgive you!" (Chapter 143, p.14)
  • (To Keima) "Yui is a more gallant, womanly, and perfect girl ... take a look." (Chapter 158, p.12)
  • (To Apollo) "That's nothing to be afraid of!! Yui is the sort of girl who'll convey her feelings even if she has to rape him." (Chapter 190, p.5)