Kiyoka Irisu

"When both of your daughters are all but dead, I think it's only logical to sacrifice one to save the other..."

- Kiyoka planning use Makina and throw her away Kiyoka Irisu is the current head of Irisu clan and the main antagonist of Makina's route in the visual novel Grisaia no Kajitsu.

Past
Kiyoka is a part of a very corrupt and powerful family but her first truely evil act was having her daughter kidnapped and her husband murdered when he tried to save her. The murder happened right in front of her daughter (who she wanted disposed of as well). The reason she did this was because he was going to expose their corruption and she couldn't have that. The fact she cared so little about her husband or daughter and was going to replace her with a daughter she had during an affair showed her socopathic nature right from the beginning.

Makina's Route
Makina mentions a few times earlier in the game that her mother hates her. Yuuji learns more about her mother when he discovers that Makina is actually a part of a powerful family (the Irisu clan) that has a lot of wealth and influence. When her family discovers that Makina recovered from the mental trauma she went through years ago they want her to become the head of the clan once again. Makina's sister Serina was in line but the head family wants Makina in charge since Serina is tied to the branch family (a part of the family that wants the power for themselves). Makina happens to run into her sister in public where Serina is gravely wounded in a car bombing. The bombing was done by the head family as revenge on the branch family for lying about Makina's health. Makina did not want to return to her cold family, since she was enjoying her life at Mihama Academy with her friends who genuinely care for her. Things get wose when Makina is shot at by gangs likely to have been hired by the branch family. Yuuji having become close with Makina and wanting to protect her decides to meet with her mother to try and fix things. When he does she shows her cold and socipathic nature. Yuuji asks Kiyoka to call off the branch family and she says she will try but ends up asking him to call Makina instead of outright listening to his plea. After talking with Makina Kyikoa says they "reached a conclusion" and hands the phone back to Yuuji. That night the bakery Makina works at is burned to the ground. The branch family seemed to respond to the orders to not harm Makina with an extreme answer. Yuuji didn't know what to do and comforted Makina that night by sleeping with her. Makina was supposed to call her mother afterward but Yuuji wasn't awake to see it. The next day Makina is acting normal and tells Yuuji that her mother would be leaving them alone. But when he goes in for an assassination assignment from his agency he discovers his target is Makina. The night before she had threatened to leak information she had found out as a child about the corruption of the Irisu. Makina's family (including her mother) had placed a hit on her. Kiyoka wanted her own daughter dead. Yuuji and Makina went on the run shortly after this and after running in circles for a few days Makina ended up being shot. After Makina was hospitalized Kiyoka had a change of plans and decided instead of killing Makina right away she would use Makina's organs to saved Serina. Since Makina was of no use to her she figured sacrificing her to save her other daughter who was in critical condition would be the best plan. Yuuji knew time was running out and decided to kill Kiyoka to set Makina free. Breaking into the Irisu HQ Yuuji finally got Kiyoka at gunpoint. The player has the option to shoot Kiyoka or refuse. If the player shoots her she dies but the player gets a bad ending. If the player does not shoot her she contacts help and Yuuji escapes the building just barely getting away. Makina is interviewed by a friend of Yuuji's from the agency he worked for who manages to get the dirt on the Irisu from her to use to blackmail them in the future and store away in their book of secrets. The agency also offers Makina help for her actions. With Makina no longer under her control Kiyoka goes to America to find Serina an organ donar.