I seriously felt like punching Leon in his pretty face honestly how rude to stick his unwanted foot in someone's realtionship, but Koganei sure told him! Like a real man
Trust me, I hate Leon just as much as the next person, but don't you think their relationship needed someone like him...? What I mean is that, if their love can survive his interference, then that just proves how much they love each other... If they were separated by something as trivial as him, then they weren't meant to be... In conclusion, Leon's situation was actually good for their relationship, and to be honest, they really needed an obstacle like this to overcome, in my opinion...
Come back to William's side he's waiting for you! (⌒▽⌒)