Oh, there was no holding John back at this point. He was pushing his hardest to bring her to that point. There wasn't a world that Pyro wanted to live in, where he was unable to provide that sweet release for Kitty. Desperately wanting to do well to bring her to that point, but naturally sometimes he would fail and pop before her, and John would have to strive better to bring her over that edge first. Regarless he was going to make sure she got hers the best he could still.
Through his own orgasm, he pumped his hips into her, but bringing one of his hands down to assist in his work. Continuing to thrust he took his thumb to put pressure on that sensitve nub of pleasure for her. Slowly rolling his thumb firmly he pushe forward with his hips to keep his length deep into her before he lost his own momentum.
The way she felt, he couldn't help still moan at her. Just how tight she was, and how she moved with him. Each thrust of his only made him gasp a little more.