After reaching the age of 18, Susumu Arisaka can finally leave the orphanage and return to his childhood home. However, he is surprised to find that five of his former high school teachers have taken up residence there before him. As they offer to assist him with his new living arrangements, they also offer him life lessons that he never expected. It's a situation that Susumu isn't quite sure how to feel about - is it terrible, or is it actually quite fantastic?