The chief character whom many brothers were born to by a remarriage of father changes in a family name called "Asahina" (Asahi) and will live with brothers in an apartment. However, the existence of the chief character who jumped into the house only of a man lets the wind and waves stand in the Asahinas who was peace till then. Brothers who brought up the thought for the chief character before long come to regard each other as a rival; - -. A love story between forbidden キョーダイ happening under one roof!　 Is the ending - - as expected?