If there are multiple secrets, then it will fly from one to the other.
This item belongs to the Beelzebub set. Collecting three items from this set will transform Isaac into a giant humanoid fly.
Notes
The familiar will sometimes hover over a pit or a Poop, indicating that an unreachable crawl space has been generated there.
Although it might seem intuitive to dig the spot open with We Need To Go Deeper! or Ehwaz, their chance of spawning a crawl space is independent and not guaranteed to work.
An extra crawl space that is added by Stud Finder won't be identified by the familiar.
YO LISTEN's appearance in Booster Pack 5 (left) vs. its original Afterbirth+ sprite (right).
Trivia
This item is a reference to the fairy Navi in the The Legend of Zelda: Ocarina of Time, who guides the player during the game with the catchphrase, "HEY, LISTEN."
The item name and description both being “Yo listen!” is a joke about how frequently Navi interrupts the player, to the point of annoyance.
Secret Room/
Super Secret Room entrance, tinted rock, or a rock with a 
Crawl Space underneath, it will fly towards it.
This item belongs to the 
Beelzebub set. Collecting three items from this set will transform Isaac into a giant humanoid fly.
Poop, indicating that an unreachable crawl space has been generated there.
Although it might seem intuitive to dig the spot open with 
We Need To Go Deeper! or 
Ehwaz, their chance of spawning a crawl space is independent and not guaranteed to work.
Stud Finder won't be identified by the familiar.
YO LISTEN's appearance in Booster Pack 5 (left) vs. its original Afterbirth+ sprite (right).
MEAT!, 
YO LISTEN!, 
PHD, G FUEL! and 
TMTRAINER are the only ALL CAPS items in the game.
The Binding of Isaac: Rebirth
