That would seem to be a not-overwhelmed emotional state over there, so full speed ahead.

Lucien does his best to inform Haru this is very good but in this case Lucien's best is incoherent mmming interspersed with attempted syllables 

"Hmm" nibble nibble "what was that again?"

"You are very go-"

"Didn't quiiiiite catch that," grope grope kiss nibble.

"You are goooooo-"

"Hmmm, maybe I should back off and let you finish your sentence, what do you think?"

"...No."

"No, I shouldn't back off, or no, I should stop what I'm doing?"

"Keep. Do-"

"Oh, if you insist." Nibble.

"Mmmmmm." Lucien is delighted to have gotten his way. Where Lucien's way is Haru having his way with Lucien. 

Really the pleasure is all not remotely all but in significant proportion Haru's.

That's really an awful lot of Haru-pleasure then, given how good of a time Lucien is having.

Haru was really very convinced during his week of chivalrous snuggling that the cute boy was a sure thing and then thought he wasn't after all and now gets to have him anyway! It's a lot of emotional whiplash to pack into a crush!

Well, Lucien discovered that his sexual feelings about men were homosexual and now a really attractive guy is cuddling him without clothes. Which wasn't emotional whiplash but was very surprising.

Haru's overall goal here is to cause Lucien to rue all that time in which he could have been having sex with Haru and instead wasn't. It was not, objectively, a very long period of time, so the ruing will have to be quite substantial per unit opportunity cost.

Lucien would be doing so much ruing if he were capable of putting enough thoughts together to do so. 

It's time-insensitive, the ruing.

Good, he's busy right now.

Yes he most certainly is.

He's cute and Haru must kiss him.

What if Lucien also kissed him back.

That improves the situation enormously.