I'd imagine they wouldn't play much of a role in the story but would still try and help wherever he can or be a shopkeeper. If I do give him major plot relevance i'll probably have him replace Dinya for a few parts of the game where he's absent. That way you still have a party member with mostly identical stats.
Credits to me, myself, and I Got the name 'Toraki' by messing with Toroko from Cave story
