No strings attached! Lance Bass revealed during a Monday, September 12, appearance on Watch What Happens Live which 'NSync member slept with the most women back in the day. Find out which one in the video above!

During a lively round of “Truth or Tweet” — where guests have to choose between answering scandalous questions or tweeting embarrassing things — show host Andy Cohen asked Bass, 37, which of his former bandmates had the most sex.

“I mean, Chris Kirkpatrick — he’s a Casanova!” the “Bye Bye Bye” singer shared. “You know, before. He’s married to a lovely wife now, but he was single before.” (Kirkpatrick, 44, married marketing rep Karly Skladany in November 2013.)

After Bass dished on his pop peer’s formerly wild love life, Cohen, 48, continued to press him with nearly inappropriate queries about the guys of 'NSync.

Asked which member he would never sleep with, Bass — who came out as gay in 2006 and tied the knot with artist Michael Turchin in December 2014 in a televised wedding ceremony — squirmed before he finally admitted, “Who would I not have sex with? I mean, all of them! I wouldn’t have sex [with] Joey Fatone. I don’t know, yeah, take that.”

This isn’t the first time Cohen has discussed Bass’ sex life on WWHL. "The most famous person I ever slept with I guess is … Lance Bass!” he told The Real Housewives of New York City’s Sonja Morgan in May 2015. However, Bass denied that he and the Bravo exec got busy in the bedroom days later on his SiriusXM radio show, Dirty Pop.

“First of all, I’m not going to tell you what I do in the bedroom,” Bass prefaced, before going into his romantic history with Cohen. “Sex is a broad term … like ‘Andy banged Lance’ — when did he ever say that? This is an old story. Three years ago we told everyone we hooked up.… Now it’s getting into who did who? I can just tell you right now, there was no Andy D going in my B."

He added: “I’m not going to tell you what went down … but it’s not what people are thinking.”

Watch the video above.

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