Shin Megami Tensei V - Uberneko (Nekomata) vs Demi-fiend [Hard] 

Its done.
So Demi-fiend has this AI quirk where if everyone else in your party nulls/drains/repels phys, he'll poke any new demon you bring in with Deadly Fury to "learn" if they can take physical damage. So by rotating new demons in with repel or drain phys, you can constantly destroy all of his turns...that is, unless he gets angry and uses Gaea Rage (after 5-6 actions if you haven't killed any of his demons). But that's more than enough time.
Had to respec Nahobino to Figment Slash to get enough damage, since Demi-fiend has 99 vitality (compared to Shiva's 40), but we got the job done.
Shoutouts to japanese Pixie VA.
-- Watch live at / nachoyacopu