Asahi, who secretly harbors strong feelings for Yuu, discovers that his step-sister Reika is actually a popular erotic manga artist. Without hesitation, Asahi becomes Reika’s assistant to get closer to Yuu. One day, Asahi calls Yuu over, and he immediately senses the lewd atmosphere. Driven by jealousy and lust, Asahi attacks him aggressively, leading to intense sex. After finishing, Reika returns home and finds out everything. Caught between his perverted step-sister and the girl he likes, Yuu is relentlessly squeezed and drained in a competitive threesome until he is completely exhausted