I'm kinda exploring various routes and runninv into an issue. Does the morning of chapter 16 also take into account your muscle level? Beforethe free time decision in chapter 15, I have relationship levels of 3 with Shaun and 5 with Legan. Plus a weight of 74kg and muscle level of 4. If I go to the Gym (and thus a muscle level of 5), then I get Shaun's house afterwards, even though Legan's relationship is still higher. Whereas if I choose one of the other two, I go to Legan's as I intended.
I guess that I'll accept that it doesn't only take into account your relationships, and also your weight and muscle, though in my opinion it should only be based on relationship. Especially because I was basing my assumption on doing high weight routes.
If it is a bug, I should probably mention that I am admittedly playing on the android version.