This is according to my playthrough so this might be inaccurate. For the shibari scene, I think Tocchan has to be a sub bottom. You must have the rope sex toy to make if work, obv. When that scene triggered for me, it was the second time I had Haato use it on Tocchan. It might be important to note that they've had sex more than 7 times at this point. For the teacher-student roleplay, you need to have the gakuran costume to be able to trigger it. The scene triggered the second time I had Tocchan wear it.