Okay @alliancesinthedark I didn't want to ramble on the original post BUT I do have Thoughts. There are two most likely candidates for this one methinks.
LegRule is definitely a possibility. This sounds like something Hyrule could babble in the midst of the act as he's lost in the dick sauce, and from years of performing and partying I bet Legend's hearing isn't the greatest. Especially with all the skin-slapping sounds in the background. He'd probably tolerate it for a little while until the idea of it starts to bother him, and Hyrule would sound fucking devastated if he stopped--although I think it's more likely Legend would hold out until after. The broody silence after sex dispels Hyrule's post-coital bliss before Legend is comfortable enough to speak.
"Can we talk about new kinks before trying them out in the middle of having sex?" "Wh... What?" "The pony-play thing. Like, give me some time to wrap my head around it before--" "THE WHAT????"
Once the confusion is sorted out, Legend's ears are going to be glowing red in the dark and Hyrule's going to be laughing so hard that Wind is banging on the floor upstairs.
The other highly likely possibility is Twark. Mainy because Dark is a little shit. Because 'I'm yours' is also a mantra I can picture Twilight repeating in the middle of a hot and heavy sesh, and the intimacy of it might make Dark feel good for a little while before it makes him feel... not-good. The dangers of getting too close and all. Dark's coping mechanisms include dorky humor, and what better way to get his cowboy to laugh than with a horse pun?
Warrtime could never. Mainly because Warriors would never say something like 'I'm yours' in the midst of sex, it's too clingy. That and Time would probably just shrug and go with it. Wars has come out with more surprising things in the bedroom, and if he's being ridden, it makes sense? Time's ridden an ornery horse or two in his lifetime. He'll just going to take a fistful of his hair to arch his back and pound him even harder.
If Wild came out with something like this during sex, Time would not mishear him. Because you know these two. This is some passionate missionary where they're cheek-to-cheek and Wild's legs are shaking in the air and Time is consumed with guilt as he just can't stop his hips from moving...
Similarly, Sky would not mishear Sun if she says 'I'm yours' and this kind of line is going to drive him wild. In fact, he might be finishing earlier than anticipated.
Re: the SkySun one at the end????? Omg??? I bet they get Freaky about their impending nuptials, too. "I'm yours, i'm gonna be your wife" and Sky nuts immediately so hard he’s blind for a second, and once he comes to again Sun has to be like "did you tell me you were gonna 'wife me up????'" And he has to be like "that doesn't sound like me wym 😳😳😳"
Also the initial "this is LegRule" impulse from alliancesinthedark is SO FUCKING GOOD. It's romantic, it's sexy, it's possessive, it's also Legend being really fucking dumb and still going even after he's like "hmm, don't like this" which. Baby. Baby boy. My guy. He deserves to be laughed at in ways that are so obviously no-stakes moments of innocent dumbassery, so he can laugh at himself, too.
And you know, little shit he is, Hyrule’s gonna hold onto that moment forEVER to hit him with "I'm a horse"/"so I was thinking about pony-play" when Legend isn’t expecting it to send him into pink-faced wheezy laugh-crying.
