She... would probably just also stay in Aather until she can't. She hasn't actively thought about what she's going to do a lot, but if she ran out of memories she'd take the Legacy Hero position in a heartbeat if it were offered to her. She's super attached to Kunzite and wouldn't leave them until she had to or if everyone she cares about left first. As for what she'll do when she can't stay in Aather at all anymore... she just kind of assumes she'll go back to doing what she used to do, and hasn't really considered that she has other options. Like, I do remember a long time Snow asked her if she was going home after Aather and her reaction was pretty much "... YES?!?! OF COURSE?!?! WHY WOULD I NOT?!?!?!" She really just hasn't ever given it super deep thought.

How would Battler feel about following Raven and Beato back to Raven's world if that were presented as an option to him?