Bizarro is definitely Jason's favorite person (by which I mean he feels safest and most relaxed in his presence) but Bizz doesn't realize it.
He thinks it's Artemis (or Dick maybe, after they made up) and he treasures their time together, of course he does, but it's always bittersweet for him because he's convinced Jay only comes to him when no one else has time.
The truth is Jason does force himself to stay away for days at a time, sometimes weeks, because he feels guilty. Guilty that he's started to fall for his best friend, the person that makes him feel so safe, and he's terrified of ruining things.
Artemis eventually hits them both over the head and makes them finally talk about their feelings.
Jason just doesn't leave again after that.











