"I can hurt you, but I won't kill you." Technically, he COULD kill John. He is just a demi-god, and of course Sherlock was a full god. But it wouldn't be easy, and it wouldn't be anything that could be done accidentally while they were fucking.

Sherlock had "accidentally" killed plenty of mortals while taking them sexually before. It was part of the fun, see how far a human could go before they were broken.

Of course, he would never do that with John.

But a bit of pain?

Sure.. that could be quite nice for both of them.

Oh, by the gods, he wanted to just take him like this, no prep, but the last thing he wanted to do was to scare John away just as they were starting to come back together.

Sherlock gave John another stroke, just to keep him on the edge. Edging could be fun. He had done it with other mortals in the past, edging his own pleasure, not thiers. Usually they were dead or near dead by then, so there was little to no resistance.

"John." He said evenly. "I can take you, or I can try to be gentle." gentle, to him was stil very rough for most, but he would try.. for John.

"I need to know, because I can't hold back much longer." Indeed he was hard, aching and dripping.