This dude Yoshiyuki loves to work out. He also loves sex, cause he's not dead. Now that he's a teacher at an all-girls school, he gets to combine his two favorite things. He decides to give his struggling students some private tuition, AKA, his dick - cause that certainly won't be hard to grasp.
Kouenji Sayuka is an Escalayer, a guardian android designed to protect the world by having sex. But when some lesbian action with her assistant Madoka isn't doing the trick, it's clear Sayuka needs some extra help. Preferably involving dick.