Oromocto, Canada - A senior shelter cat named Max earned himself a real online following and a hysterical sign on his cage because when he's feeling sassy, he dolls out a smack.

Max the cat was only at the Oromocto and Area SPCA animal shelter for a few weeks, but his caregivers knew to be careful around the feisty critter.

This puss just can't keep his paws to himself.

He's not afraid to show his annoyance with a swat ... or seven.

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"He’ll reach his arm right out through the cage and smack if he needs to," the shelter's manager Tracy Marcotullio told The Dodo.

She added that Max likes cuddles, but "if you don’t read his cues properly, then you’re getting smacked."

Max is like a "cranky old man," she added.

While the kitty's hits are harmless, they inspired the shelter's staff to make a hysterical sign for the animal's cage.

"It has been x day(s) since I smacked someone for no reason," it reads.

The longest Max the cat had gone without smacking someone is four days, according to The Dodo.

"It’s not that he’s a bad cat," Shelter Manager Tracy said. "He just gets overstimulated, and when he’s had enough, he’s had enough."

Since the shelter started sharing pics and videos of Max with his silly cage sign to their Facebook page, they've been bombarded with calls, and he has become a viral sensation.

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Tracy said that Max's stardom has helped "bring attention to other cats in the shelter. He’s helping his buddies get adopted. It’s a win-win."

The shelter shared an update that Max, despite his wicked ways, has gotten an upgrade in homes and now been adopted too. He is so missed at the shelter that staff has put a cardboard stand-in in his cage – a substitute without his swating antics.

"I’ve been Max smacked a few times now, even when offering him his favorite treats," his new owner wrote.

"We are taking it slow and know he will eventually come around with time, love and understanding while still respecting his personal space."

"Wish us luck!" she added.