Travis Kelce is opening up on what it's like to date the most famous singer on the planet ... saying the craziest part is folks watching his every move -- meaning he can no longer relieve himself on the golf course.

Kelce chopped it up with Will Compton and Taylor Lewan on the "Bussin' With The Boys" podcast this week ... when he peeled back the curtain on his romance with Taylor Swift -- and denied they're purposely trying to get more eyeballs on them with their adventures.

"We're having fun with it, man," Kelce said. "Yeah, being a couple, dude. You already know. It gets thrown out there as it's like we're trying to seek attention every now and then. But it's like, we're just enjoying life and having fun, going to hockey games, kind of introducing her to some more of the sports world."

The Chiefs' star tight end was asked if there was one aspect of being in a high-profile relationship that has caught him by surprise ... and it didn't take him long to come up with a response.

"I'm just playing golf and all of a sudden in the trees there's a f***ing guy with a camera," Kelce said. "Like, 'Oh s***, I gotta go to the restroom now. I can't just go over here to take a piss.'"

The 35-year-old said the last thing he wants to wake up to is his privates published all over the internet ... so now he has to resort to plumbing.

Kelce also weighed in on Swift's free schedule now that the "Eras" tour is wrapped ... and he said she will be up at Arrowhead cheering on the squad this season.