Nivlac and Sebboh

Nivlac and Sebboh are the evil counterparts of Calvin and Hobbes from another dimension. They used to be good, but it is unknown why they have turned that way. Nivlac and Sebboh somehow teleported inside Calvin and Hobbes' duplicator, but they didn't know what they were saying. They had to teach him English, so they did. Then for some reason, after 8 visits they turned evil.

Credit to Andrew Martin of DCAH.

Appearance
Nivlac has a black shirt with blue stripes on it, while Sebboh is a lion that has white and blue stripes, while on Calvin and Hobbes: the Animated Cartoon Adventures they have inverted colors with Nivlac having red hair and a yellow T-shirt while Sebboh has orange stripes and black fur.