Velvet Crowe starts the game as a 16-year-old living in rustic Aball with her younger brother, Laphicet, and her widower brother-in-law, Arthur. During the Scarlet Night, Arthur - retaking the name Artorius Collbrande - sacrifices Laphicet to reawaken Innominat, his god, and end the demon epidemic by suppressing humanity's free will. He turns Velvet into a Therion - a demon that eats other demons - and then throws her into a secure, isolated cell in a high-security prison for three years, where she is forced to consume demons for her survival. Her dead sister, now a Malak - basically an angel - busts her out of prison, and sustains a mortal wound defending her. At her request, Velvet consumes her, and obtains her signature powerup for her Therion Arm.
After escaping, she cuts a swath through the Abbey - Artorius' forces and the leading religion in the world - while gaining allies. She burns a port, aids fugitives, falls in with pirates, destroys a fortress, imitates doves, assassinates a priest, constantly commits public indecency, and more. After finding out that her Innominat has fused with the body and soul of her dead brother, she has a breakdown. After moving past this, she then systematically kills and eats the souls of Artorius' four most powerful underlings and shoves them into a volcano. Doing so awakens the four Elemental Empyreans, beings who oppose Innominat's power and bring massive change to the world with them.
Velvet and her companions then fight through Innomniat's body, reaching and defeating Artorius himself. Velvet kills Artorius herself, and then uses her Therion powers to trap Innominat in an eternal cycle of devouring and being devoured. She seals herself and her brother-turned-god away, dreaming of a happy life where no one died.
Fate/Shipping Wars (by Leolab)
Combatants: Arata Fukamori & Chris Northfield, Velvet Crowe & Eleanor Hume, Adam and Eve, Wes and Rui, Sypha Belnades (Netflix) & Trevor Belmont (Netflix), Arcueid Brunestud & Shiki Tohno, Ellen Kohagura & Kaoru Mashiko