love?

Mareg: Suggested by an inhabitant of Nanan Village, I don't think this is very likely to happen (even if Mareg had survived). Their relationship appears to be more of a parent-child or teacher-student one (although the former one fits better, I think, because obviously they share friendly feelings as well - at least towards the end).

Roan: If one wanted to, you could find minimal hints to this one during their conversation in the nightsky, but I doubt it nonetheless. After all, Roan is more of a child than a teenager and Tio - although she might look like one - is far older than all characters in Grandia 2 (of course, her "personality" itself is not, but she has memories of all the time she has existed before, too). Plus, they don't really suit each other in my opinion.

Ryudo: No chance, he's being shared between Elena and Millenia already... lol.

After all, I can't really imagine Tio with any boy or girl - it might be due to her childlike (not childish) behaviour and innocent manner, or because I just like her too much; but I think she's not the type for having a relationship.