Ecchi na Shimai no Double Chikubi Seme Kairaku

Buy official english version on Yuki is a girl who just loves to tease boys' nipples and always posts her play antiques on social media. One day the protagonist, who was a big fan of hers, sees a text posted on her feed that says, "Seeking a submissive boy with weak nipples".. and, of course, he signs up right away! After being the lucky guy that is selected, he finally meets his adoration.. Yuki. But it would seem that Yuki's older sister, Natsuho, has also tagged along for the event. That is how the long and arduous nipple torment at the hands of two sister, Yuki and Natsuho, began.