Teacher MoRina enthusiastically welcomes students back from vacation break but has no idea that every time she lifts her arms up, she unintentionally exposes her belly button to the whole class! MoRina is a very animated math teacher, so the students get an eyeful! On occasion she flashes her thong back when bending over too! She never realizes that her thong is showing, but she eventually realizes she exposed her belly and tries to downplay her obvious embarassment.