Ryuutaro's brain lost the ability to keep up the moment Hayato started actually sucking and maybe that was good because before he'd just had a mass of letters in his head that didn't actually make much sense either.
To put it simple, he'd been pretty terrified, because no matter how often they slept with each other, he still was the most innocent and simple person. But then through the mental keysmashing and very much real blushing, he just had to moan. Sanity aside, this felt just really good. He was getting aroused to fast...
And it was embarrassing and awkward and oh god... Meeting Hayato's eyes he blushed even more, a rare thing for him, then he had to turn his head away a bit. But at the same time...
"...d-don't stop"
Even if he wasn't able to play over how he really didn't know what to think his body had the priorities set straight out.