His lips are very soft, yes, and his tongue is wet when he touches it to Matt's lips.

(He hasn't been able to achieve the laboratory conditions to verify this, but he suspects there is no temperature at which any of his bodily fluids would freeze.)

He wraps his arms around Matt and pulls him a little closer, smiling into the kiss. He learned a lot from Jim, but what he learned was mainly Jim; with Matt he feels he ought to start from the beginning.