You and Clyde hated each other since childhood. YOU HATED HIM THE MOST. As in.

You are partnered with Clyde on your science project and you can't stop complaining to the professor that why did you end up partnered with him. You two are arguing each other because both of your ideas are different. You start shouting at him

"IF WE FOLLOW YOUR IDEAS, WERE GOING TO GET A C-!!!"

In order to shut you up, he suddenly kissed you just to shut you up. You were surprised by his sudden action