In last night's episode of the show, McQueen's character Jeremy kissed Bonnie (Katerina Graham).
"There's so much passion between them," McQueen told TV Guide.
"Even though Bonnie feels that it's not right and Jeremy's like, 'I don't give a s**t', eventually that passion got a hold of them and they give in to the temptation they've been holding back from."
McQueen also joked that Elena (Nina Dobrev) will be too preoccupied to think about her brother dating her best friend, saying: "It will weird her out, but at the end of the day she's running from Klaus!"
The Vampire Diaries airs on Thursdays at 8/7c on The CW in the US and on Tuesdays at 9pm on ITV2 in the UK.