Fight as Unknown Angel Boss
Beat the game on Normal or higher using a character with a Devil alignment.
Fight as Geezer Devil Boss
Beat the game on Normal or higher using a character with an Angel alignment.
Fight as Kurara
Enter Arcade mode and highlight Nanase. Press Select Up Down Down L1 L2 Start. Highlight Nanase and press Start to scroll through the two versions of Nanase and Kurara.
Fight as Kyohya
Enter the code Fight as Kurara enter Vs. mode and highlight Verny. Press Select Left Right Up Down R1 R2 Start.