I really like Ivanova so the thought of her bonking Byron is horrible to me, but it does make sense in a messed up kind of way. Look at her love life. The racist leader of the anti-alien terrorists in "War Prayer". Talia, or should I say her evil PsiCorps implanted personality. Marcus, the vestal virgin who died before she could tell him she loved him. And now comes along a pretentious emo wank British telepath with long hippie hair. Sounds like just the kind of mistake she would make in her grief.
Claudia once said she hoped they'd make her failure of a love life a running joke. She was hoping they'd hook her up with a bizarre alien or two.
All this time I never brought it up but I was wondering where she was. Yeah "And a Rock Cried Out" kinda brought it up, but it was a trick to get Refa in place. Delenn still had Lennier, Mollari still had Vir, but what about Na'Toth. That side of the story was great. Loved the scene with Mollari being all drunk and getting noticed trying to release her. Also, G'Kar has been awesome this season. More proof of that with this episode. 

