In episode 32, Arkhan and Temptel are attacked while searching for Reina in limbo. It seems that despite the fact that all angels and devils are forbidden to have any kind of affectionate relationships. Arkan and Temptel snark at each other Like an Old Married Couple.
Arkhan: (with complete sincerity) Do we have to argue about this right now, my dear? Temptel: Of course my esteemed college, I wouldn't want to upset you. But we have to figure out how to eliminate these monsters before they tear us to pieces!