Emerson wasn't going to prolong the conversation with an 'are you sure?' follow up question because this was one of those situations where if it was thought about for too long, it got intimidating, and then the more it was thought about, the less appealing it got, and then arousal would fly right out the window and Merlin knew he didn't want that to happen. He was just surprised that Reed actually agreed to it. He met his eyes for a moment of acknowledgement, then started to kiss his neck again. He blindly found his wand -- which he'd kept at arm's reach with the intention of using it on himself, originally.
This wasn't Reed's first time, but it was going to be the first with the aid of the magical charms that made it a bit easier to take than going at it raw with just a bit of lube. Emerson thought briefly about talking him through it, but figured that would probably only freak him out more. Reed was more action than words when it came to doing things, and Emerson figured he'd play into that. His free hand found Reed's arousal again and he started stroking him slowly, wanting to keep the arousal going and the focus there. While kissing his neck, he performed the charm on Reed that he always used on himself for this, then tossed the wand aside.
He wasn't going to say anything like, 'tell me to stop if it's too much' either, because he knew Reed would anyway, and because he didn't want him thinking about it like that. He didn't want Reed thinking at all, except about the pleasure he wanted to give to him. Emerson sucked on his neck, all the while stroking his erection slowly, but firmly. His other hand strayed down further, teasing the skin between his erection and his entrance, only occasionally ghosting his index finger over the one area on Reed's body that he'd never fully explored.