【The live-action adaptation of a smash hit with over 2.4 million downloads!】 While their parents are away on a trip, Akari and Ma-kun end up staying home alone. As the caring Akari washes Ma-kun's back in the bath, she accidentally sees his erect penis. Embarrassed and angry at being seen, Ma-kun says, "Show me your boobs, sister, then we'll be even!" Akari readily agrees, which confuses Ma-kun instead. However, upon seeing Akari's large breasts, Ma-kun can't hold back and pounces on her, saying, "I want to be spoiled... Yeah, because Mom has always been gone." Akari feels tenderly towards Ma-kun and decides to help him with his first ejaculation.
