Kara kind of has an aversion to people doing it. She's a supernun. Maybe she decided long ago that if she ever did it with a guy she would break him so she came to terms with never doing it ever.
Mon-El is right that she's a Kryptonian snob. He's going to need to break her figurative walls down before he can break her literal walls down. Right now he lacks the motivation to do something like that, especially when the MISS TESCHMACHERs! of the world are around, so lets see what happens.

LOL, yeah, good points.
"I'm the ultimate badass,you do NOT wanna f-ck wit me!"Hudson,Aliens

Considering the amount of times Superman and Lois have had sex in the comics just fine, I'd dare say Kara could do it with any human. Hey, the Flash has children, and he had to worry about the whole vibrating someone into goo thing.
Man of Steel, Woman of Kleenex, Larry Niven is shaking his head at how popular it is, 40 years later, an essay he wrote tongue-in-cheek.
I am a man with Asperger's Syndrome, so please forgive me if my posting seems weird.

I'd rather see Mon-El and Winn.
Don't Jdg a Bok by Its Move

Eww. That's her cousin.

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