Shakugan no Shana S03 E24 The End in the Distance

Johann and Pheles give up their existence to give way to a new form of life, they son, Justus. Many Flame Hazes also leave for the new world. Yuji intends to reverse all the damage the Denizens caused to Misaki City, including the return of Hirai, effectively undoing all the relationships that Shana has built with everyone.