Though the couple have been spotted out together recently, this is the first confirmation of their romance. Mendes previously dated her Riverdale co-star, Charles Menton. The pair called it quits in late 2019 after more than a year together.
Vaughan recently photographed Mendes' Riverdale love interest, KJ Apa, and he shared the shirtless pics on Instagram last month.
In addition to Apa, Vaughan is also pals with another well-known star, Tallulah Willis, the daughter of Bruce Willis and Demi Moore. The pair posed for a cute pic together in 2016, which Willis captioned, "Dumpster & Bumpy take Hollywood #hereforLeo."
Mendes is currently in Vancouver quarantining with her Riverdale co-stars as she prepares to finish filming season 4 of The CW teen drama and to start on season 5. She and co-stars Lili Reinhart and Madelaine Petsch have been having lots of fun together, creating a group TikTok for their fans, which includes some epic choreographed dance moves.