Angus Cloud Honored by His 'Euphoria' Costar Dominic Fike During Concert

Angus Cloud's death was top of mind during his costar and friend Dominic Fike's concert -- and he delivered a moving moment, reminiscing with the audience about Angus.

The singer and 'Euphoria' star -- who acted alongside Angus during Season 2 -- addressed his costar's sudden passing during his show Tuesday night in Houston ... and shared some very personal feelings with the crowd.

Check it out ... Dominic says he just lost a friend, and then goes on to muse about the larger implications of that -- and how getting the news instantly made everything else so trivial.

You can tell he's getting pretty introspective here, openly wondering whether performing the concert was appropriate considering the tragedy -- but then he answers his own question, saying Angus would've wanted him to go on and do what he loves.

Dominic also had this to say about AC ... the guy operated on a certain wavelength and his energy was palpable, making him standout among a star-studded cast, including Zendaya.

TMZ broke the story ... Angus was found dead in Oakland Monday, and his mother called 911 to report her son didn't have a pulse. Cops discussed it as a possible overdose, and Angus' family has indicated he may have taken his own life in the wake of his father's death.