Even though he loves big boobs, the girlfriend he finally got to have sex with hates sex with small boobs. He's so frustrated that he goes to a boob pub... and to his surprise, his girlfriend's little sister, Rina, is working there. What's more, while she's serving another customer, an older man is groping her big boobs. Later, unable to resist, he calls for Rina, and, fooling her surprised sister, he gropes her boobs, secretly fucks her and cums inside her without the pub knowing! From that day on, he's groping his big-breasted sister's boobs even at his girlfriend's house, and it's like a boob pub!