His horror past might be the reason why he turned evil.

This causes Herb to run through the party naked, telling everyone that the clothes have come to life and turned evil.

The original hints at but never explains why the evil fairy turned evil.

He looked a lot like Mimi did before she turned evil.

Katsuya huddles into a corner with fear and his facial expression suddenly turns evil.

He and Dragon still respect each other despite Dragon having turned evil.

This clears the way for real innovators like Google (although even they are turning evil recently).

Kintoki is forced to strike down his old friend, Masakado who has turned evil.

At this point, Shirley realizes he has been abandoned and turns evil.

He took the book to prevent his master from turning evil.