3. Litwick
What is it: A candle Pokémon, which is a Ghost/Fire type which is native to Unova and seems pretty innocent in its game sprites but it is in fact creepy as f**k.
Why is it creepy: Imagine if you will, this scenario. You are lost in a forest in the Pokémon world, its freezing cold and pitch black. Suddenly as you're just about to give up hope, you see a flame on a Pokémon's head, whom you ask to leave you out of the forest. Aw, so nice of it to comply and help you. Actually no. "While shining a light and pretending to be a guide, it leeches off the life force of anyone who follows it". Litwick isn't trying to help you out, it is trying to take your life energy and leave you for dead. Run the hell away!