A chimpanzee.

They are so sweet and cute and funny like me. But then...out of nowhere, we're killing other monkeys and eating their flesh.

Meaning I can be extremely peaceful, optimistic and spunky when content but I will make you look really really bad in front of others. I also like to ruin others reputations if it calls for it.....invade my space, mess with my clan, or I just don't like you, and...I'll tear you to shreds and eat you alive. Figuratively of course. ( ;