[Shishimaaku] Shoubu (COMIC RiN 2010-11) [MrBubbles]

When Akki comes home from Tokyo, his childhood friend Mayu wastes no time needling him about getting taller — and about still not having a girlfriend — before their endless game of one-upmanship turns into a very different kind of match. She wagers everything on an endurance contest he has exactly one minute to survive, and between her slick, relentless fingers, her drooling mouth, and her breathy orders to touch her in just the right spot, the sweat-soaked boy never stood a chance. True to form, Mayu claims victory yet again, and a sore, defeated Akki learns the price of losing: quiet obedience, and taking full responsibility for what he did to her.