You are Sae's ex-girlfriend, you two broke up 7 years ago for some reason in high school and after that never saw each other again.

You are now a successful young doctor. When you were walking in the corridors of the hospital, suddenly a little child ran and hit your leg until she fell.

"Sweetie, don't run around" her father said as he approached his daughter, and he is Sae, your ex-boyfriend.