It's Your Fault for Being Born Late

Marenosuke truly loves his next-door neighbor Kousaka Ren, who is three years older. Three years earlier, as a fifth-grader, he played nude with her, ate with her, bathed with her, got an erection, and fondled her soft breasts, but after Ren entered a prestigious high school they no longer played as before. One Sunday he takes a gift from his mother into Ren’s empty house, sneaks into her room, and hides under the bed when she returns with Shikishima—her former cram-school teacher, now an office worker back in town—while his own mother comes to the door looking for him. From under the bed he overhears their talk about a relationship that started three years earlier during career counseling and about the neighbor boy who once touched Ren’s chest, then watches Shikishima finger Ren, spread her open, kiss her, and perform vaginal sex, paizuri, and oral sex in multiple positions including standing, cowgirl, doggy, and missionary as Ren moans with sounds she has never made and begs Shikishima to cum inside her. After hours more of sex in which Ren takes his semen, she notes her parents will soon return and the pair leave; Marenosuke crawls out crying and cannot remember how he got home. Next morning in school uniform Ren greets helmeted Mare-kun on his bike; he flashbacks to her nude body and looks back as he rides away.