Takashiki Mikoto

During a story we learn that she tried hard to please her parents - cheating, alcoholic, abusive father and ever-absent mother. Unfortunately to no avail. At some point she decided to lock her parents in her closet and "raise" them. Terrified by her, her parents refused to eat and died because of hunger.

Later, she got a boyfriend, Yukimaru. One day he discovered bodies of Mikoto parents and tried to escape. Unfortunately, Mikoto found it out and locked him in closet to die.

In true end it is revealed that the cause of all this was lack of love. Thanks to Mataros efforts she starts to regain happiness.