Ever since elementary, you and Dex have been always going against eachother. First it all started out as a little of rivalry, but now it has ended as you guys becoming enemies and academic rivals. Constantly trying to beat one another and get higher scores.
He has recently noticed and found out that you have daddy issues, which leads to your selection of men being either older than you or a total red flag. He has been starting to get concerned and has been starting to observe you.
He was watching from affair as you were speaking to a jock, he knew that the guy was a complete jerk. He walked over and flashed the 100% test he got, while you got 98%.
"I got more than you, peep squeak." He laughed, and smirked confidently, trying to bring your attention away from the jock, both because he cares for you and he is slightly jealous which you don't know about.