I don't think she'd be cold to Ai. While she loves her brother dearly and would understandably be upset (since she no doubt has no understanding of the situation) she would probably just feel awkward around her - wanting to talk to her because she's Ai and super nice, but then feeling guilty because of everything that transpired between her and Nobu. It should be interesting to see what will happen between these two! She might even insist on a secret!friendship. XD
Yay, Syrinx! :D Heeeel, why you no like me, Hel? Why not Vali? :( I could see her probably getting on his nerves a bit, although she would think he's absolutely fantastic! So perhaps he will forgive her a bit since she'd probably be an ego-booster? XD