Ni Nin No Ototo (LUNA)

[Machine Translation] Kei, an adopted child of the wealthy Shiraishi family, has two younger brothers born after he was taken in. The older brother, Naoto, is taciturn, and the younger brother, Akito, is not afraid to speak his mind. Even after being shunned by their mother and leaving home, the two brothers were more important to Kei than anyone else. However, on the night he broke up with his girlfriend, Akito suddenly came to him and said, "You must be lonely since you broke up with your boyfriend, aren't you? I'll comfort you," and forcefully embraced Kei, who resisted. Kei was troubled and asked Naoto for advice, but Naoto also had a crush on Kei. Although he is the older brother, he is caught in the clutches of his brothers and drowns himself in their lewdness. Kei, terrified of the forbidden sin, eventually makes a big decision...

裕福な白石家の養子・圭には引き取られた後に生まれた二人の弟がいる。寡黙な上の弟・直人と物怖じしない下の弟・明人。母に疎まれ家を出てからも圭にとって二人は誰より大事な存在だった。だが、恋人と別れた夜、突然訪ねてきた明人は「カレシと別れて寂しいでしょ?慰めてやるよ」と抵抗する圭を強引に抱いた。悩んだ圭は直人に相談するが、直人もまた圭を-。兄でありながら弟たちの執着に囚われ、淫らに溺れていく。禁忌の罪に怯える圭は、やがて大きな決意をするのだが…。