The 18 year old Susumu Arisaka finally returns to the home of his childhood after many years in a children’s home and is looking forward to an independent life as a high school student. However he has to pay off the mortgage and therefore sees no other way but to look for some housemates. And quicker than he can say lodger, five charming young ladies move in with him, who are also his teachers. He quickly realizes that his quiet life is over now, because he even has to give up on his own room and share the bed with his “Mamas”. But not only that, they never take their eyes off him and watch over his education and give him private lessons to save money on the Juku, because a shortage of money blights their life. And as if that is not enough, they try to set him up with Fumitsuki Nanaten...