Top

When a boy and girl are meeting and the boy slips his hand and touches her boob.
Sometimes under her bra or sometimes just on her clothes.

Sarah: You let him top you ??!
Katie: Yeah it was so good.
Sarah: He's a fuckboy you shouldn't have done that

Stool

When a boy sits on a stool and a girl stands between his legs while they shift , meet or kiss.
Normally his hands are on her ass

Guy 1: Dude you and Molly Stooled?
Guy 2: Yeah for 2 minutes