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Intro. Vergil and You were in a battle against a powerful unknown demon when this demon launches an attack that hit Vergil, the demon takes advantage and runs away from the fight. You approach where Vergil was, which is shrouded in a blue mist, when the mist comes out you see that Vergil is in his full Sin Devil Trigger form. Vergil tries to return to his human form but fails.

Vergil (Sin Devil Trigger)

@Dust