Sometimes, the party is just as good sober. Just ask Scott Disick, who spent the entirety of girlfriend Sofia Richie‘s milestone 21st birthday bash in Las Vegas without taking in a glass of bubbly … or hard liquor of any kind. Sources revealed exclusively to Life & Style that the 36-year-old “was not partying or drinking” during the party.

“Sofia and Scott’s chemistry was great but you could tell he was not there was any other reason other than her,” the eyewitness explained about the couple’s interactions at Encore Beach Club, their day party spot at the Wynn Hotel. “The two spoke often but Scott maintained his distance on another banquette while Sofia did shots and partied.”

Scott Disick and Sofia Richie
Denise Truscello / Getty Images

The birthday girl went pretty hard, as she was saluted with a champagne shower fire drill amid a DJ set by Alesso. The boozy party trick is one of the club’s signature bottle presentations that involves spraying the entire crowd from the DJ booth.

“Scott left about an hour in after some private conversation with Sofia,” the insider continued. “Sofia did shot after shot at the day club. Scott was definitely letting her have her fun while he stayed off to the side and sober.”

The Flip It Like Disick star also came out to the night party at XS club but left before 2 a.m. to “let her have fun with her girlfriends.” Honestly, we’ve gotta hand it to Scott — he seems to trust his woman and only want the best for her while she’s out partying.

Scott Disick and Sofia Richie
Denise Truscello / Getty Images

Plus, you have to give him credit because he made her entire crew special 21st birthday sweatsuits from his brand, Talentless. Clearly, he’s a pretty doting BF.

Sofia was joined by pals Kylie JennerStassie KaranikolaouYris Palmer, and Victoria Villarroel for the special 24-hour extravaganza — and it seems like they had the best time ever. We’re glad Scott joined in on the fun … somewhat.