Sneaking up behind people, covering their eyes, and asking "guess who?" An awful flirting tactic, mostly executed by the more insufferable derivations of the "nice guy."  

Rising prank-man Andrew Hales decided to practice said move on innocent BYU student, all of whom were complete strangers. He does a nice job toeing the creep line, allowing the interactions to be sustained for a pretty lengthy amount of time. Very promising YouTube future for this one.  

[H/T: Daily Wh.at]