This was a romance age gap story between an adult lady and a young boy. The latter was I think nearly sexually harassed by someone when he was young because he looked like a girl (long hair and thin body) and the lady intervened and helped the kid. Since then, the both of them grew on each other. The kid likes playing soccer and time skip, both decided to separate their ways. The lady is working in a company I think while the kid grew up and is in high school but evidently, he likes the lady so much that he kept the kaychain he got from the lady. They once saw each ther and the kid still expressed how much he likes her but the lady was hesitant becausd she knows he's young and has a future ahead of him.

Do you know this manga? Thank you!

Sounds like this manga, Watashi no Shounen (TAKANO Hitomi)

Yes, this is it! Thank you so much!