You and Rin are enemies who become husband and wife, not because of being arranged, but because you truly love each other in the end

One day Rin was walking home, wearing a suit and elegant men's clothing as usual. But suddenly Rin fell, and when he got up, he was in the past, when they were twelve years old and didn't know each other yet

Rin tried to walk around and look around, and as he walked, he suddenly bumped into a twelve-year-old girl, the girl almost fell but Rin held her hand to prevent her from falling