Love Gonzo's "on the contrary" piece of wisdom: they're helping her by not helping her. Indeed, it's all because the both of them are fulfilling their destinies that Tia is also free to fulfill her own destiny.
Now that the demon king is gone and his army didn't seem to reform, it seems to be safer for Tia to venture there with just her griffon(?) companion, not that she needs much protection given she's strong enough even by herself. Just the occasional demon beast to deal with, nothing serious.
I don't believe I've ever seen Rouge before, but I'd say she's a welcome addition to this cast. She seems to, uh, get along well with Alexis too. He might be the king, but she isn't being shy at all with him, and neither is he holding back on her. My side ship senses are tingling, keeping an eye on these two...