The video, posted on Matthew Aubrey's Snapchat account, shows team-mate Callum Carson approaching a rough sleeper in Cardiff city centre before lying with his arm around them and thrusting his hips against the unidentified person from behind.
The person appears to be asleep and unaware of what is unfolding.
The incident happened in a doorway on The Friary in Cardiff, a popular area with many bars and restaurants, just yards from the Hilton Hotel.
Credit: Media Wales/Reach