Blue Exorcist (2011)

S5E8 The Blue Night

Shiemi feels uplifted when Rin unexpectedly shows up. Her voice brings Rin back to awareness, prompting him to travel back in time to witness everything unfold. In that earlier time, Satan's possessed form starts to crumble, spiraling into chaos. The Blue Night finally commences. As mighty clergy from across the globe are consumed by blue flames one after another, the Myodha Sect in Kyoto, the Three Sages in the Vatican, and Shiro along with the Knights in the Japan Branch face an overwhelming crisis.