Thor would be lying if he said he weren't enjoying this, but it's equally putting him on edge - there's a danger to this strange coupling that he's never experienced before. The slight nerves, the singing of his blood before a battle has always excited him, of course, but never the way this is right now. Thor is more than happy when a mouth is suddenly on his erection, mouth opening with a small surprised gasp that immediately morphs into a contented chuckle - but then he recalls who it is and his body can't decide whether it wants to wither away or moan.

The danger of wanting is an unexpected third party in this, coaxing Thor on as much as it makes him want to pull back. He's never been one to shy away from a challenge, but this goes against social mores, if not laws.... And feeling Loki's soft but quick tongue against the underside of his tip only encourages his brash side, the one that doesn't care and, if anything, is spurred on by the threat.

Feeling bold and perhaps to reassure his kin, he sighs, "Loki." It's not a wanton growl or anything quite so extreme, just a simple word as though they were merely speaking...and it sends a throb through Thor's lower body, a tingling up his spine.