This archangel needs brother/sister angels, humans he's the guardian angel of, demons that know his secret! and tempt him to fall, a nemesis to try to strip away his smiles and make him go berserk, a devilish witch trying to harness angelic and demonic powers.
And for my second character: The best friend, the NYPD detective partner, the sparring partner, a witch to try to help him break a curse.