There was just so many issues, and early on in the game both Shuu and I came to the conclusion that really Yuri and Flynn behaved like they had a really bad break up in the past.
My Flynn will always watch out for Shuu's Yuri, and give him 6 am calls (or earlier) about what Yuri should and shouldn't do. And I really enjoy that dynamic, they are still close, even if they aren't together in my mind.