[Hoshino Fuuta] Slumberland Special Plan (Wakaba to Issho)

With grandpa, uncle, and the whole family downstairs drinking and laughing, little Mio feigns sleep as her older brother figure slips into her room and locks the door behind him. Paralyzed under the covers and completely at his mercy, she bites back her cries as curious fingers slip beneath her pajama shorts—until her own hand discovers something stiff and warm she has never felt before. By morning she greets him with a blushing giggle and a heart-spangled 'I forgive you!', while a suspiciously radiant grandpa at breakfast suggests their secret Slumberland special plan was only the beginning.