It's not that simply. First of all, Mithril got nearly whiped out in COMO, what means he has no support in the next novel, in which he is in some third world shithole with no clues about Chidoris whereabouts. He participates in Gladiator AS fights to get money, befriends his teammates and gets into a slight relationship with a female team member. But just when he thought he could forget Chidori and build a new life, shit happens, the girl gets killed and he gets heavily wounded. I'm too lazy to write about the next two novels, but trust me, Gatoh is an excellent writer, it's really worth reading.