Magical Canan

Magical Canan (まじかるカナン) (also appears as Magical Kanan) is a magical girl eroge developed and published by Terios. It was later adapted into a 13 episode-long television series by AIC studio.

Tree of Eternity (Episode 13)
Fennel corrupts Chihaya/Carmain into a fallen magical girl using the dark energy seed. However, Natsuki managed to undo the transformation by purifying Carmain.