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The feeling of nails digging into his side.
The poor attempts at dirty talk.
The heavy breathing.
All of that was expected when Mephisto topped. Shiro couldn't stand any of it, but it was the only way to keep the demon under control during his rut.
"You know- Ah- you should be more grateful that I chose you to bear my children- "
He whined, gasping everytime one of his thrusts went especially deep, the deeper part of his hole feeling so much tighter than the entrance. God, he didn't know how to handle being on top, it was always too much and not in a good way.
And none of it felt good to Shiro. But he had to bear with it. He felt his lover pound deeper and deeper into his ass. He let out a soft groan as one of his thrusts hit his prostate.
"Fuck- Babe, you know I can't get pregnant, right?"
Shiro snarkily said, hoping to quell some of the fire Mephisto had.
It didn't work.
"Shut- shut up- "
Mephisto growled out, mangled and desperate. He let out a strangled hiss, and then he sobbed out another moan. The demon dug his nails into the hips of Shiro.
He wanted to breed Shiro so badly.
So, so badly.
But he couldn't. He couldn't and he knew he couldn't. Yet, he still tried. He needed to see his lover's stomach filled with his children.
One of his hands moved down to forcefully jerk off the priests cock. He heard somewhere that conception is easier if the woman is having an orgasm. Obviously, that wouldn't work in this situation, but he had to try.
That earned him unamused groans, and soft curses.
"Shit- The fuck are you doing?"
"mmm... It'll be... Haaa- it'll be easier if you orgasm."
Was he really that stupid?
Shiro sighed, he wasn't going to break the news to him again. They both already knew it wasn't going to happen.
But that didn't stop the merciless, rythmless thrusts that pushed against every single part of Shiro's insides. That rammed so deep, he swore he could feel Mephisto inside of his fucking stomach.
"Gonna breed you so, so full... Gonna make you a mommy for me, Father."
Shit. The addition of Shiro's formal title got him hard. Damnit, what he would give to have Mephisto beneath him instead. The way he'd kill to be slamming into the demon, having him scream out 'father' over and over again. To have him whining and begging.
The feeling of teeth sinking into his skin snapped him out of his thoughts. As he got used to the pain he realized he was close. Fuck, he was close.
He didn't even have time to process the warm liquid invading his insides, filling him up. The hasty, needy thrusts as Mephisto's hand speed up. Shit. He couldn't cum from this, he couldn't-
There he goes. Hissing against the bed, grinding down against the demons hand. He clawed at the sheets, mumbling out various curses as he rode out his orgasm, still filled to the brim with dick.
"You're going to be such a good mother."
Mephisto purred into his ear, as he nuzzled against his shoulder. He gently let go of him and started massaging his stomach, where his fogged mind believed their children would be growing.
Shiro really had to stop saying yes to this.