Miki Koishikawa lives a normal life until her parents announce their divorce. She resists the idea, but everything changes when she meets Yuu Matsuura, the handsome son of the couple her parents are marrying into. Their families merge into one household inside a huge house, and Miki and Yuu discover they are falling in love. They must navigate their own emotions, the attention of others who also desire them, and the twists of fate and luck that come their way.