*that situation* was where Rui didn't want to accept him while Yahiro had become his pillar/friend/fckbuddy for 16+ years. Remember he *jokingly* asked if he wanted to date and his face was just horrified? Yeah, that gotta hurt and if this wasn't BL, a normal person wouldn't have gone back to him.
what do you mean by "did play quite a bit"? is it doing with a girl even though they're in that situation?