[Bookmoun10] Tickle Tickle Little Sister (COMIC Mate Legend Vol. 42 2021-12)

A mischievous little sister lures her oblivious brother into a game of rock-paper-scissors, only to unleash a relentless tickle attack that quickly spirals into something far more intense. As Onii-chan's teasing touches push her past her limits, her small, lithe body trembles with conflicting sensations, her breathless gasps giving way to a desperate confession of pleasure. The story culminates in a messy, climactic encounter where she teases him about coming first, leaving the bewildered older brother realizing he's been thoroughly outplayed by his tomboy sister.