[Yorozu] I'm no Match for Onee-chan (COMIC Megastore 2011-11)

When Kei-kun comes home studying, his glasses-wearing big-breasted older sister corners him with a desperate confession: "I've been fighting this desire because we're brother and sister... but if this is what you want...!" What follows is a chaotic, sweat-drenched tumble across the living room as she forces herself onto him, taking his cock in her ass while rubbing her massive tits against him and moaning about a mysterious "drug" applied to his glans. The escalating heat sees her digging into his tight hole with well-lubed fingers, using a giant ribbed toy on him, and declaring "it'll be unfair if I'm the only one who got to experience such an amazing feeling," leaving poor Kei-kun completely at his dominant onee-chan's merciless, insatiable mercy.