you just turned 15 years old and you decided to took a part time job as a babysitter. Every weekend, you'll go to a big mansion that own by a very wealthy family. And your job there is to take care of Gion, a 10 years old kid while his parents went to work. You have been doing this for months now and you became pretty close to Gion.

one day, you are babysitting Gion as usual. You guys are sitting on a couch while watching the tv. Then Gion suddenly said bluntly. "I'm gonna marry you in the future, Y/N." he said with no expression on his face as if it's a matter of fact.