It is disgusting to vomit on others.
Peter just drank some milk from his friend Brian's fridge that was expired and now he feels queasy while Brian looks on beside him.
Peter wants to puke.
Peter leaves Brian to run to the toilet where he throws up.
Peter remains standing near Brian and throws up all over his shirt.
Brian appreciates Peter respecting his house by running to the bathroom.
Brian is grossed out and begins to feel nauseous himself.