to give some a lexing is to spin a series of lies to them, many of which should be about yourself, in order to make them like/respect you, and particluarly to sleep with you.
Cornelius gave Mary-Sue a lexing, and as a result succesfully laid her ass.
A fan club based out of Robinson Middle School that are diehard fans of a student named Lexing Wei. They take the club very seriously and have tried multiple times to get his autograph.
Guy 1: omg you know the Lexing Wei Fan Club?
Girl: Ugh, not those weirdos.
Guy 2: You can’t spell weird without wei!