Chapter 0
A classmate suddenly became my older brother...? High-school student Shinozaki Aya can help but take care of others. The only one to relieve her burden is her classmate and close friend Haruki. But what will happen when they learn about their parents remarriage to one another? Will they really be able to become siblings?
Chapter 1
A traditional girl with a grandma's mindset, Kijima Rio wants to avoid getting involved with the "ill-mannered youngsters" at all cost. As fate would have it, she must work with a "youngster". And the fun begins...Â