Given how much attention and focus is put on him, it's hard for Asterion not to be my favorite character. He's just so well written. What I expect for his story is....complicated, I hope to see greater conflict with the MC, particularly surrounding the armband promise, and whether or not the MC is tricked into breaking the promise or is forced into an ultimatum where he might have to(both likely involving a wily snake). If there were interactions I'd like to see between characters, I'd love to see something like Kota and Luke trading off the Cobalts for half the week with each other like a divorced couple taking turns watching the kids.