Onegai, Nugashite.

Please, listen. There’s a curse on this school. Anyone who does something “impure” gets stuck unable to remove their underwear. Only the protagonist’s right hand can break this curse—his name is Kamite. When Kamite explains to the girls that they’re cursed and he’s the only one who can help them, well… naturally, they’re not exactly thrilled at the idea of some guy taking off their panties!