The busty younger sister, unaware of her brother's advances, goes on a rampage, thrusting and pounding until she's climaxed. (Hina Nitori, PPPE-196)

"During sex, when there's a break, the hymen will regenerate and the vagina will be plugged." The ignorant younger sister, enraged by her brother's lie, went berserk. If it's plugged, that's bad, so she took it upon herself to insert her brother's penis. Knowing the pleasure level, even when her brother said "I'm going to ejaculate," she remained oblivious, refusing to notice that he'd already ejaculated inside, and continued thrusting. Completely ignoring the ejaculation inside, she even accelerated her hip movements.