故事主要讲述了就读于圣克罗尼亚学园高中部的溷血儿羽濑川小鹰，在某一天看到了美少女三日月夜空一个人愉悦地说着话，之后两人便开始聊起关于如何交朋友的话题。而没想到夜空建立了一个以交朋友为目的问题社团──邻人部，各种问题美少女先后申请入社。
Joon hyeok is preparing to pass the exam for level nine government staff. Since this is his third attempt, he is sure to pass the exam this time. He moved into a boarding apartment as part of his father's special measures to help his son with his studies. But what awaits Junhui in the luxurious house is not thick textbooks, but two free and unrestrained women. Joon hyeok began his cohabitation with the owner of a boarding apartment full of sexy beauties, Aqiong, and the nurse Dal lae, who exudes sexiness from his face and body. Since then, Junhui has started studying women every night instead of his books.
