scope on (one)
slang To regard or look at one with sexual attraction or interest. He spent the whole date scoping on other girls, so, no, I don't think it went very well. There's some girl at the bar scoping on you, Chris—you should go over and talk to her.
scope (on) someone
tv. & in. to evaluate a member of the opposite sex visually. He scoped every girl who came in the door.