It's a big blow for D.J. when she catches her boyfriend Kevin experimenting with booze at a dance...and an even bigger blow when Jesse wrathfully accuses her of same.
D.J. is at a school party. She catches some boys drinking beer and is shocked to see Kevin drinking. When Jesse arrives, D.J. has her back to him, and a beer can in her hand. Not knowing what had happened, he jumps to the wrong conclusion.—RightWingGuy