Cheko

A maid, or rather, a mysterious organism, that comes from the Maid Planet (in the anime, Maid Country). It looks like she sprouted, rather than being born. According to her, she's "the end of human evolution." She has a frilly thing on her head (it looks like a typical maid headdress) that can turn into a boomerang, cutlery, or even tissue paper. Also, the hair on her head can be used in similar ways. If anyone else wears it, it will self destruct or suck blood out of the person wearing it (it doesn't work on Kanato's mom, though). Her dream for the future is to become a sumo wrestler. Her head and body can be easily separated. Taking off her head is no problem at all. Up, down, left or right, her body is structurally symmetrical in all directions. Normal-sized humans can enter her body through her mouth. She has blue, short hair. Her eyes are green. - Wikipedia