I previously posted this on the Evil Conversion thread in Transformation section, but I thought I should also post it here since it is an AP TF.
This is from an old cartoon named "
12 Senshi Bakuretsu Eto Ranger". In episode 33, a catgirl is tricked by an evil mastermind into becoming stronger and evil. The transformation takes place between
3:01-3:43
According to
rick404 from the Evil Conversion thread,
"
Character: Chocolate ショコラ transformed into Nyanma ニャンマー premise is based of the 12 animal Zodiac which leaves the Cat out. Chocolate gets excluded from the good guys bitter she gives into the dark side basically becoming one of the baddie's generals. "