[Brothers Conflict] Character Conquest System

Asahina Rui is the eighth son of the Asahina family and also their adopted child. His relationship with his brothers isn't very good. But the day before the start of high school, he inexplicably picks up a "Brothers Conflict Character Conquest System." The System keeps persuading Rui that it can improve his relationship with his brothers. He agrees to everything the System says because he has always hoped to get closer to them. But gradually, he realizes that his feelings for them, and theirs for him, seem to have changed. Their love for one another is no longer so pure...