SHAKUGAN NO SHANA: SEASON II

The heated bond between Shana and Yuji is tested as their paranormal adventures continues. The Flame Haze fends off supernatural foes by night. By day, she contends with a classmate who's also after Yuji's heart. Emotions flare as a suspicious transfer student who resembles a recently defeated Denizen clings to Yuji. His training rises in intensity when they catch wind of a revered warrior in search of her lost lover—who will stop at nothing to extract the power keeping Yuji alive! (Source: FUNimation) — Description from AniList community (anilist.co).