Kyodai no Rule (Nichibun Comics)

[Machine Translation] Rule 1: Treat each other naturally as family members. Rule 2: Set a time limit. Rule 3: Never cross the line. That's our "rule of today". Mikage Aiba, a high school senior, and his brother-in-law, Tomoki, who is one step younger than him. The older brother loves "rules" and "order" and the younger brother is loose and rough, but they have been brothers for 12 years since their parents remarried and have always gotten along well with each other. But that winter, when Mikage decided to go to college, their uncontrollable feelings broke the "order" and a new "rule" was established for the two of them.... A beautiful and tranquil dramatic love story between brother and brother-in-law by the up-and-coming author, Katsura Kanai!

ルール1、家族として自然に接する。ルール2、期限を設ける。ルール3、最後の一線は越えない――。それが俺たち「きょうだいのルール」。高校三年生の相場みかげ、1つ違いの義理の弟・智機。「ルール」と「秩序」を愛する兄、ルーズで大雑把な弟、と性格は正反対だけど、親の再婚で兄弟になって12年、ずっと仲良くやってきた。けれど、みかげの大学進学が決まったその冬、抑え切れなかった想いが「秩序」を壊し、ふたりだけの新しい「ルール」が定められた…。気鋭の作家・金井桂が描く、美しく静謐な義理の弟×兄のドラマティック・ラブ!