The punch had completely snapped its head, only a pipe connected the had to the body, Phoebe felt her stomach churn at the sight and forced herself not to throw up everything he had just consumed. The monsters skin began to heal itself and it's neck snapped back to it's rightful position, letting out squelching sounds.
That was more than enough for Phoebe and melora who turned their faces and hurled out the entire content of their stomach, Phineas felt the same way but was better at keeping the contents of his stomach in and controlling his disgust.
They had all seen gory scenes but there was something about monsters that were off, seeing the disgusting creature regenerate torn parts was more than the could handle.