I Left My A-Rank Party to Help My Former Students Reach the Dungeon Depths!

I Left My A-Rank Party to Help My Former Students Reach the Dungeon Depths! Yuke, a red mage, quits his A-rank party, Thunder Pike, because he feels they don't appreciate the support he provides; while seeking a new party, he encounters one of his former students, Marina, who invites him to join her new D-rank party.