Chapter 11:
One week in:

When Chekov and McCoy's relationship started, McCoy was afraid that he wouldn't be able to keep up with an eighteen-year-olds sex drive. He was certainly more "practiced" in the subject than his lover, but definitely not more eager. Chekov was not a virgin the first time they made love, initially a surprise to McCoy, but after getting to know the frisky Russian, more believable. Chekov seemed to be, for lack of a more sophisticated word, horny all day long. McCoy was afraid he was going to have to deny his lover too much. He couldn't have been more wrong.

Being with Chekov seemed to have unlocked a new ferocious sex drive in the older man that he never knew he possessed. It only took a few intense nights for McCoy to realize this. He was always ready for some love with Chekov, and Chekov never hesitated to initiate it. But come on, there had to be some place to stop for the older man.

"Oh… Fuck, Pavel, this is amazing," McCoy moaned into his lover's mouth.

The two were in McCoy's quarters, standing on their knees facing each other on the bed. They both had the others dick in their hands and were pumping at a unison rhythm. They tried their best to stay on each other's lips, but both the men were so into it, it was hard to keep a kiss going for long.

"Ah – ah! I'm going to cum!"

And with that Chekov came hard. McCoy came a split second later with a loud moan. The white sticky substance coated the men's chest and all they could do for a few moments was lay down and pant. McCoy reached over for the box of tissues he kept by his bed, but before he could reach them Chekov glided over to the doctor and cleaned up his chest himself. McCoy did admit that Chekov's tongue felt much better than some tissues. He returned the favor when his Russian lover was done and they both slipped under the covers, foreheads touching, for some relaxing cuddles before they had to get back to work.

After several minutes of silence McCoy spoke up.

"Did you know this was the tenth time we've had sex this week, and it's only Thursday morning?"

"You've been keeping count, sir?"

"hmm, I guess I have."

"There is not a problem with that is there?"

"No, of course not. You have awoken a passion in me I didn't know was there. Good job, kid. I just don't want to run out of steam early."

"What do you mean?"

"Well, you wouldn't want us to use up all of our desire within the first week, would you?"

"I don't think we will have that problem. Or at least, I won't."

At this McCoy shifted his head up and looked at Chekov in the eyes. He had raised his eyebrow in that way he does when he doesn't agree with something.

"Are you calling me old? Do you think I can't keep up with you?"

There was playfulness in his voice – he wasn't actually angry, although he might have felt a little challenged.

"N- No, sir. I would never say that!"

"I'm just kidding, Pavel. And stop calling me 'sir'. It may be erotic during sex, but it's just weird now."

"Yes, sir – I mean – Leonard."

They stayed in their position on the bed for another twenty minutes before McCoy had to leave to report back to sick bay. McCoy gave Chekov a last kiss in bed, got up, and went to pick up his uniform shirt off the ground where he had quickly discarded it an hour ago. When he bent down to pick it up, he heard a snap as his back cracked. He let out a groan of pain and held his hand across his back. He looked over at Chekov, who had a playful smirk on his face.

The Russian questioned the aching doctor, "Are you sure your age isn't catching up, Leonard?"

McCoy frowned at the lucky young boy and replied, "Shut up, kid. Just you wait until your youth is gone and you can't jump around like a spazz anymore. Then I'll be the one laughing!"

Chekov let out a giggle as his lover put back on his shirt and walked out of the room. Chekov was pretty certain he would never get old.