Rebirth: Magic Beast Contract & Revenge+

Elara, a low-ranked student, is killed with her F-level Black Bear by top student Liya in an ice apocalypse. Reborn to the beast-assignment day, she finds Liya also reborn and seizes the Black Bear. The bear secretly reverses their contract, while the SSS White Wolf Caesar bonds with Elara. Together they take revenge, survive the cold, and bring sunlight back to the frozen world.