I can't be the only one smelling a flash forward ending.
What else could it possibly be?
The previous chapter already ended with “we both love each other, but in different ways,” so we either get a repeat of that in more detail (not out of the question, of course) or a flash-forward to some time when the age gap has become “safe” (Uta out of college and working, maybe?) and Kaoru has snapped gay.