IbitsuИзнанка; イビツ; 砸扁你; Distorted

A boy went to take his trash out late one night, and found a strange, creepy, lolita woman sitting amongst the garbage bags. She asked if he had a little sister, and he answered her, hurrying afterwards back to his apartment. When he looked out the window, she was gone. Who is the strange woman, and why does she give him such a bad feeling?