Ena Seishuuin[]
Susanoo appears to have a close relationship to Ena as she wields his sword, Ame no Murakumo no Tsurugi, and she calls him Grampsy.
Godou Kusanagi[]
Susanoo seems to have a great deal of respect for Godou. Whether this is simply because he's a Campione, or because of how Godou acts and uses his powers, is unknown.
Godou kusanagi
Princess with Glass Eyes[]
