Rule 1, treat each other like family. Rule 2, set a time limit. Rule 3, don't cross the final line… These are our rules as brothers.<br>High school senior Mikage Aiba has one younger step brother, Tomoki. While the elder sibling prefers rules and order, the younger is more easy-going and loose. Despite their two opposing personalities, the two have been close ever since their parents got remarried 12 years prior.<br>However, when Mikage gets accepted into university, the feelings they can no longer push down shatter their "order," and a new set of rules are laid down between the two…<br>The spirited author Kei Kanai pens a dramatic, yet beautifully tranquil love story between two step siblings!