Neutered?

My friend Allison adopted a stray cat and took him to the vet to be neutered.

“I’m about 90 per cent certain he’s been fixed,” the vet said.

“How can I be 100 per cent sure?” Allison asked.

“Watch to see if he does any ‘male’ things.”

“He already lies on the couch all day,” she said. “If he starts hogging the remote, I’ll bring him in.”