相馬美咲（Souma_Misaki）/相姦遊戯2・GAME.Ver（Soukan_Yuugi2・Game.Ver）

相馬 美咲

誠人の通う学園で音楽教師を務めている実姉。誠人の母親代わりでもある。弟想いだが、おっとりした性格で押しに弱い。誠人が自分のことを必要以上に慕ってくれていることも理解しているが、どう応えて良いのか困り果てている。

Souma Misaki

She is Masato's older sister and a music teacher at the school he attends; she also acts as a mother figure to him. Although she cares deeply for her younger brother, her easygoing nature makes it hard for her to stand her ground. She is well aware of how intensely Makito dotes on her, yet she is at a loss as to how she should respond to his feelings.