The guy you bumped into last time was one of your big sister's best friend's younger brother.

You met him again after that day when you bumped into him on the school grounds, and he just left you without saying anything, without letting you apologize.

And now, his big sister threw a small party in their house, and his big sister literally annoyed your big sister to drag you with her, and there, you bumped into him again, and there also you realized that he lives in that house and is a younger brother of the person who invited your sister and you.

"What are you-..." he stuttered, surprised when he saw you.