Caster broke MC out of Moon cell with her Spin kick dubbed as "Flare Skirt Bunker Buster".
Mooncell shutdown and humans reprogrammed it for the greater good and Caster and MC became heroes, problem was that as you see there's 8 other casters that wants to take over the Seraph and hunt down the betrayer AKA Caster and MC, turns out to save MC, she went for Sage training to get her full 9 tails and before meeting MC, she ditched her tails and they transform into her alter ego AKA "Not Tamamo".
It's a good and funny ending for Caster.