[Kaitou Yuuhi] The Penis Caste 1&2 [itsy]

Transfer student Miyuki Nanahama expects an ordinary first day at his new all-boys school, until a whistle and a wandering hand reveal the academy's strangest tradition: a caste system ranking every student by cock size, where the bottom rung is dressed in sailor uniforms and expected to serve everyone above them. Demoted and flustered, Miyuki watches classmate Iori get thoroughly broken in by the higher caste while onlookers jeer, then finds unexpected tenderness with the sweet Kaede over shared first kisses and a desk full of toys. What begins as humiliation slowly curdles into curiosity, as the newest member of the bottom caste wonders whether serving his schoolmates might be exactly where he belongs.