She begins to hate the baby even before he is born as something impure that will ruin her beauty.Р”В«ecause of this, SubaruРІР‚в„ўs mother who is already extremely unstable, put Subaru through the worst childhood- such as calling him filthy abomination and asking him to kill her,trying to harm him ,or to the point of even giving him a silver knife that can kill vampires. Christa became mentally ill and bipolar,at one side loving Kalrheinz as her РІР‚Сљkind big brotherРІР‚Сњ and at the other side hating him like РІР‚Сљthat man that dirtied herРІР‚Сњ. But when she found out about Karlheinz wanting to use her for creating an incest born child in between them for his experiments only,she started to struggle in between hating and loving him and became mentally ill.By that time she was already pregnant with Subaru which made her condition only more complicated. Christa loving Karl as a brother,didnРІР‚в„ўt declined the marriage even though her consent was never really requierd. The reason Subaru gave the heroine a knife is because he wanted her to kill him then he said if she canРІР‚в„ўt do it she should kill her self.Р”В®ven though Christa knew very well what she is getting into ,and that her РІР‚Сљolder brotherРІР‚Сњ(her close blood relative Karlheinz she views as a direct sibling) already had two other wives,she preferred to self deceive and think that he only uses them and loves only her. He considers himself filthy and ignorant because of the ways his mentally ill mother have endlessly called him in his face while either trying to kill him or begging him to kill her. His mother, Christa, described him as being gentle, even though she was the main reason for his horrible childhood and later for his lack of trust in females. HeРІР‚в„ўs also an extreme sadist, but despite all, can occasionally be sweet. HeРІР‚в„ўs a delinquent type, kind of violent and loves to damage things. There is a tsundere side of him that not only the heroine can see but also his brothers,and he usually gets teased about that by Laito.

However, due to his very traumatic childhood, he easily gets angry and resorts to violence, going as far as to break everything when he gets extremely angered.

Subaru is the silent type who usually sleeps in a coffin, which is also inside his room. He is usually alone and never cares about whatРІР‚в„ўs happening around him. Subaru can be described as the loner type. He wears it with the standard uniform pants. There is a small chain loop on the bottom left side of the jacket. His school uniform consists of the black school blazer with the sleeves rolled up to his elbow and a black shirt underneath that is ripped near the bottom and a white shirt underneath it which is longer and also ripped at the bottom. He wears the necklace with this outfit as well. He also wears black pants and has a black sweater around his waist. In MORE,BLOOD (fandisc), he wears a black jacket with a black shirt underneath. He also wears black jeans and a necklace that is wrapped twice around his neck with a golden or bronze colored key on it. The ends of the red shirt appear to be ripped/shredded.

In Diabolik Lovers ( game), he is usually seen wearing a black jacket with a red shirt underneath which has a brown belt around it. His bangs are parted to the right, covering his eye. Subaru has white hair - though it is often shown to be a light silvery color with pinkish tips - and blood red eyes like his mother.

Diabolik lovers subaru preequel