Due to something that happened when he was younger, Yuji Kuga is anthrophobic and has no experience with women. The only person who can touch him is Leo, the childhood friend who has always looked out for him. Deciding that he can't trouble Leo any more than he already has, Yuji tries to get over his trauma at college, to no avail. In fact, even his twin brother, Reiji, tells him enough is enough. Then, one night, Yuji is surrounded by gay men and dragged to a literal "hole in the wall" bar; an establishment where the male staff service customers by offering their lower body through a hole in a wall. It turns out that Yuji was mistaken for Reiji, who works there part-time. He's required to pleasure customers without any explanation, but for some reason, rather than hating it, he revels in the satisfaction the unknown man on the other side of the wall brings him again and again. For the first time, Yuji experiences the delights of someone else's fingers and tongue. He starts thinking that doing this might just help him overcome his phobia... And he can't forget the ecstasy he felt while he was being thrust into. So, the next day, he heads to the bar once more...