Garan nodded, thinking that Nate was asking him if he were sure. It was all the encouragement he' needed, seeing as though Nate didn't at all look like he opposed what was about to happen. Therefore, Garan lowered his lips to Nate's arousal, kissing the head tentatively.
As Garan had never done this before, he was now incredibly unsure of himself. He knew what felt good - he had the same parts as Nate, obviously - so it wasn't so much that as it was. . . well, how to do this without making it seem like he was totally inexperienced.
Never mind that Nate knew he was; that wasn't the point. He wanted to do this well. Garan licked along the slit in the head before taking the tip into his mouth and sucking gently. No going back now!