Los Angeles, California - When mailman Andrew Smith first came across this mail slot on his route in LA, he was greeted on the other side by a snarling, scratching beast of a cat. Unfortunately, this became a daily occurrence!

Numerous TikTok videos from the "other side" show exactly what goes on at this address, where Frankie the cat lives and defends his territory every time Smith appears at the letterbox slot.

The drama can be seen in one of the clips that went viral last month, in which the cat is already lurking for the letter carrier.

When he finally tries to put one of the letters through the slot, Frankie jumps up in a flash – and does everything he can to scare him away.

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Thanks to a door camera, it can be seen that one of the letters occasionally flies around Smith's ears in these situations, as Frankie watches him push it back.

His owner doesn't find all this too funny, although many TikTok users are amused, which is why the Californian recently wrote a letter to the deliverer.

"Hello Mailman! Sorry about our cat, Frankie! She is crazy but very cute," she wrote.

"What is your name & favorite cookie? Want to say thank you for everything!"

Smith didn't miss a beat and also replied by letter, revealing, among other things, that his favorite type of cookie is white chocolate macadamia nut.

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Frankie's owner knew what to do and left a gift bag with his favorite cookies on the doorstep the next day for the mailman to find.

Does that make things ok? Certainly not!

"Frankie is committed to this feud," his owner says on TikTok. Oh, well... maybe the cat will eventually find some much-needed chill.