User blog comment:DeathGodPrayer/Talk About What You Want!/@comment-24501441-20140203173259/@comment-1359322-20140203173742

A reincarnated Devil remains their position even after he/she becomes independant. Like Tannin is still Mephisto's Queen even after he becomes a King. Same thing goes to Issei. If there is anything different, it would be the fact that the Reincarnated Devil can't use their traits in Rating Games where they serve as King. For example, Issei can't use promotion of Rating Games where he is a King, aside from that, nothing much changes.