Kinda confused

I looove this couple and this author. That being said, I am a bit confused at the source of their misunderstanding - I mean, semantically. First, Kaji talks about that same thing from vol. 1, that is, how he wants to treasure Yura's body, which would be why Yura shouldn't push himself solely to accompany Kaji's pace. But then, Kaji starts talking about HIM not being good enough to pleasure Yura, which would be why Yura is pushing himself to begin with. So which one is true? Logically speaking, the last option seems to fit better in the plot, but I think all that dialogue scene is somehow hard to follow: both reasons make perfect sense separately, but put them together and it's kinda ?????