Onihime VS is a manga series written by Dall-Young Lim and illustrated by Soo-Hyon Lee. The manga started serialization in Kill Time Communication's male-oriented manga magazine Comic Valkyrie since October 29, 2007.
This series follows a Japanese high school student who makes a deal with an Oni for 10 million yen in exchange for his life in a year.
Setsuna's only desire is for his sister to live a happy life. Weak, frail, and constantly bullied, Setsuna believes he's nothing but a burden to his sister and decides to take his own life. As he prepares to jump off a bridge, a mysterious man appears and presents him with an unusual offer. He offers to purchase Setsuna's life in one year after which Setsuna will die in a manner the man chooses. In exchange, he will give Setsuna's sister 10 million yen at the completion of the contract. Skeptical at first, Setsuna accepts. The next morning, thinking it was all just a dream, Setsuna awakens to find two beautiful women sitting beside him. They are Kanna and Rena, Oni princesses who have come to protect Setsuna. The catch; one of them gets to eat his heart in one year.
- Setsuna is in high school, and has been raised by his older sister ever since their parents died. He was born with a weak heart, and has been harassed and humiliated through most of his life. After overhearing a talk between his sister who had borrowed money from some loan-sharks to pay for bills, he feels so guilty that he contemplates suicide thinking that it would be for the best. Literally on the edge of the bridge, he confronted by the "Middleman" who offers him "10 million yen" for his life in a year, after Setsuna accepts he tells Setsuna to drink a "Banrikou" as proof of their contract. He awakes thinking that it was all just a dream until he notices two girls sitting over him. Their names are Kanna and Rena, sisters from the Oni clan who were sent there to protect him until his "Banrikou" heart is matured a year from when the contract was made. If he is attacked by a demon, the sister he thinks of first, Kanna or Rena, will come and help him out and whoever is summoned the most will eat out his heart and thus obtain the ultimate form, and will then become the leader of the clan. It has been mentioned that since drinking the "Banrikou", Setsuna's heart has been a lot healthier due to the "Banrikou" maturing. It is also said that Setsuna's heart is special, from the fact that he can summon both Kanna and Rena at the same time. Though shy and quiet, he has shown bravery when the odds are completely against them for the sake of protecting the ones close to him.
- She is Setsuna's kind hearted older sister, who after their parents' death she has taken over as the parental figure. She tries her best to take care of him, going as far as to get money from a loan shark to pay for a heart operation for Setsuna. When Kanna and Rena appeared, she was thrilled to see that her brother was "getting friends" and let's them stay as long as they want, completely unaware of the fact that they will kill him in a year.
- She is a classmate of Setsuna and she and her two friends (Satou and Mirozawa) regularly pick on Setsuna. However, this only covers up the fact that she has a crush on him (one that she has a hard time even admitting to herself). Throughout the chapters it is obvious that she is warming up to Setsuna, even going as far as to try to make him drink a Love Potion, but will regularly revert to her angry persona when things don't go her way. She lives alone in an apartment (which she bought with her "pocket money", revealing that she is quite wealthy) because she can't stand her parents. She later becomes the master to the Oni Princess' cousin Hina after destroying a magical orb and saving Hina's life.
- Middleman is a demon who dresses up as a gentleman: complete with a suit, top-hat and monocle. He seeks out people who no longer see a value in their own life and offers them a deal, their life a year from that day for a large sum of money. To seal the deal he has the person drink a potion called the "Banrikou", which this potion also marinates the organ in question to be devoured by the one who paid for it after the year. This potion gives off an aroma which lures other demons. He also appears to be a bit of a flake, as Kanna commented that he always forgets to inform the customers what they are getting into.
- Kanna, also known as the "White Princess", is the elder of the sisters of the "Oni Clan", she wields a powerful "Golden Staff" that acts as a bludgeoning weapon. The powerhouse of the two sisters, Kanna is loud and brash and likes to take the 'direct' approach to problems, which usually means beating the crap out of it. She also loves to play tricks and tease everyone. Despite her brash personality, she cares a great deal about her family and will deny her pride as a demon and clan princess to see them safe and sound. Being very voluptuous, she does tease Setsuna on occasion with her body, trying to get him to think only of her. In the first chapter she becomes Setsuna's homeroom teacher to keep an eye on him and she got a job in a hostess bar to help with expenses since she eats 4 times as much as normal humans, though demons do eat more than a human. After an event of drinking a Love Potion made by her cousin Hina (It was a Love Potion for males), her memories were erased, thus having a personality completely opposite (she is shy, polite, kind, etc). Through Setsuna's caring personality and willingness to protect her (even if he gets beaten up), she has fallen in love with him, and obviously gets jealous when he is with Arima. Though Setsuna believes that the feelings that she is showing for him is only due to the Love Potion she drank, it is suggested that she still might have these feelings for him after her memory returned and that she remember what has happened during the memory loss. Proven when the group was in the train coming back from their adventure to cure her memory loss, when Kanna caught Setsuna looking at her, she blushed and glanced away.
- Rena, also known as the "Black Princess", is Kanna's younger sister and also a sister of the "Oni Clan". She wields twin swords, "Life Spirit" and "Death Spirit", one black and the other white, which is the reason why Sestuna usually calls for her as she as the ability to remove the demon without harming the host. A mute, she communicates (comically) by writing her words out on portable tablet/pad. Her demure nature makes her much more amiable among normal humans. Like Kanna, she also got a job but as a maid waitress at a otaku restaurant, at which she is extremely popular. While she is 'quiet', she does have quite a temper when it is riled up, usually in protecting Setsuna from other demons and from Kanna's attempts to undermine her own bid for his heart. She also has a dark sense of humor, where when Kanna lost her memories, Rena stated that she was the older sister and that she would kick her to the curb if she didn't get her memory back soon.
- The "Red Princess". Described as a loli, she is Rena and Kanna's cousin. She studied hard for ten years for the chance to take the Sage Test, only to have it canceled because of the Banriko Heart challenge. Furious by this (and from all of the practical jokes they would play on her in the past), she tried to defeat her cousins by tricking Arima that she needs to get Setsuna away from them, as they were going to kill him. When Arima discovers that Hina was also going to kill Setsuna, she destroyed the Orb, which then causes Hina to become Arima's servant. the result making Arima treating her very badly. Through the use of her long smoking pipe, she is able to summon Smoke Familiars which resemble large stuffed animals. She also likes to make potions and have a good knowledge of medicine and Tonics.vi:Onihime VS