I really don't know if it's a healthy relationship or not.

It issssssss...

I think it starts off a bit unhealthy since they don’t really sit down and discuss the student x teacher dynamic and how it’s gonna play out when people start to find out. This lack of communication created most of the angst and almost caused them to break up. However, the scene with the rings and the shooting stars is when they realize that instead of seeing themselves as student or teacher, they should see themselves as two people who are in love, and that their lives have improved because of it. I read somewhere that the issue of “what if people find out” was dealt with because it’s inevitable that people will find out, that’s something you can’t control. What you can control is how you react to it and move on, and Kousuke and Masahiro have decided that they will deal with those challenges together, no matter what. To me, that is what fixed up their relationship and made it so much more healthier. That fiasco taught them that they must communicate with eachother and share their feelings- for example, Kousuke realizes that he can’t just keep Masahiro out of the loop and that they have to talk things out more, and Masahiro learns how to share his true feelings without feeling like a burden to Kousuke (both have massive growths!!!). So at this point it’s clear that their relationship is healthy :)