Ebisu, the traveling shopkeeper, follows you around during your adventures. The only thing he loves more than our in-game currency, the Ryo, is seeing your immortal body die over and over again. It's grim, but it's good for business! With a painful past of his own, he's not that sympathetic of your troubles, but he does sell helpful "Mercenary Missions." These allow you to send minions to far-off towns to pickup other items for you while you continue to battle.
Ebisu can also help you customize your character's appearance or speed up your training of new powers. He's almost as wise as he is cranky, so you should see what other secrets he knows, but don't tell him we told you that!