At this point in time, Matthew wasn't interested in them taking their time. His sense of chivalry may have kept him from letting things progress so far before now, but he wasn't fighting his desires at the moment.
He wanted her just as badly. He seemed to want her more with every passing moment.
Something about the way she reacted to his touch only increased his desire for her. There was something undeniably sexy about the way she moaned and cursed for him and he smirked when she panted that she was close.
Matthew's own release came just after hers. He'd been fighting to hold off, but the moment he felt her muscles tighten around his fingers, he gave up that fight and he came with a loud groan even as he worked to keep his fingers moving while he milked her of her release.