[Futamaro] Hatsujou Bishoujo no Midara na Mitsutsubo Ch. 1-6 [Kuraudo]

A doting older brother can't hide his longing during the family's trips to the public bath, and when his little sister finally invites him to put it inside, her trembling defloration becomes a confession of just how much she loves her onii-chan. Their secret deepens across chapters until a playdate with her bespectacled friend Rika turns into bound-wrist teasing and spread-legged begging between the two naked girls, right up to the moment the brother barges in on their game. Futamaro's soft, blushing heroines and shameless nakadashi finishes carry this six-chapter run of sisterly devotion and exhibitionist mischief.