Ariana Grande's making sure fans know "the boy is mine" ... stepping out with Ethan Slater for a rare date night out.
The "Wicked" costars attended the 2024 Stanley Cup playoff game Saturday at the Amerant Bank Arena in Sunrise, FL, where they cheered on the Florida Panthers ... a team Ariana grew up watching as an FL native.
While Ariana and Ethan tend to keep a low profile -- he is still in the middle of a divorce -- the duo's been stepping out more together lately.