My bad. False alarm, turns out they aren't cannibals. No one will tell me what they were actually doing, but Pineapple Head promised to tell me when I'm older, and since they're Miniskirt-chan's friends they can't be bad.

Psst, Miniskirt-chan, Odango-chan, I don't mean ta worry you, but...I think Lipstick-chan and her friends might be...Cannibals!