Shūsuke is the son of the Takanashi family. He is rather perverted, often keeping large abundances of porn magazines and always looking for panty shot opportunities. Recently he continues to use term which "not betraying Nao" implying he loves her, or at least wishes to have her see him as a good older brother. He does admit to feeling some interest in Nao, not brother–sister interest, but girlfriend–boyfriend interest. He is not aware of Nao's knowledge of either the truth about their relationship or the fact she knows about all his dirty habits. He is quite the heavy sleeper, making Nao wake him up almost daily for school, though Nao does likes this way for she can do the things she wouldn't normally do to him when he is awake, in short this is when she shows her true self.