Brooks Koepka Admits He Waxed His Ass After Losing Bet to GF Jena Sims

Brooks Koepka and Mr. Miyagi have something in common -- they both believe in a little "Wax on, wax off."

The PGA superstar did a little Q&A on IG with his girlfriend Jena Sims on Monday night ... where the golfer was asked about a rumor that he waxes his ass.

Not only did Brooks answer the question, he totally owned up to some cheeky body hair removal ... and even provided an explanation.

"It is very true," the 30-year-old said ... "I lost a bet to Jena!"

That's when Jena chimed in -- adding, "And, we may or may not have had some friends in attendance!"

Hot wax on the ass party?!!

Jena couldn't believe Brooks talked about it on social media -- saying, "That's a deepest, darkest [secret]."

To be fair, the secret was kinda out ... remember the his and hers thong photo from their 2019 trip to the Maldives?!

We shoulda known!!!

Brooks is currently the #12 ranked golfer in the world -- after winning the PGA Championship in both 2018 and 2019.