Trouble Majo Shiken: Kaichou-sama to Tennenkko wa Majo Shimai! Nakadashi Ecchi de Maryoku Hokyuu wo Otetsudai!

Minato is a university student. One day, when he goes to the school, he sees Eriko and Sayako fighting against a monster using magic. While they pay attention to him, they are attacked and get cursed by the monster. He is forced to take the blame and told to sleep with them to relieve the curse....