drop (one's) guard(redirected from drop her guard)
drop (one's) guard
To become less guarded or vigilant; to stop being cautious about potential trouble or danger. We'll wait long enough for them to drop their guard before we launch our invasion. There will always be people in this business looking to exploit you, so you can never drop your guard.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.