Full-time feline photographer Andrew Marttila from Washington, D.C., captured blissful expressions of various cats on catnip, which he used to compile a book, “Cats on Catnip”. The photographer dedicated his time to capturing the euphoric expressions of kitties high on catnip – and the results are absolutely hilarious. (Photo by Andrew Marttila/Caters News Agency)

A cat Loki with a pair of distinctive fangs has quickly become one of the most famous felines on Instagram thanks to evil-looking face. Loki, who now has more than 23,000 followers online, was adopted from a cat shelter by her owner Kaet, who explained on in a posting that she knows very little about the cat’s distinctive appearance. Adopted from a cat shelter, nothing was mentioned to his owner Kaet about her kitten's unique features.

Khan, a five-year-old male White Bengal tiger, looks on inside an open-air cage at the Royev Ruchey zoo in Krasnoyarsk, Russia, October 21, 2016. (Photo by Ilya Naymushin/Reuters)

See What Happens when This Cat Enjoys a Less Than Tasty Meal

“Hi! My name is Seiji Mamiya. I hope my cat pictures would make you all happy!”

These romantic sepia shots show lovers enjoying quiet, unguarded moments together – but the subjects are not besotted couples; they are fearsome big cats. Freelance snapper Goran Anastasovski has devoted more than 10 years of his life to photographing big cats and other animals. The 46-year-old from Macedonia aims to emphasize their human qualities in his photographs. (Photo by Goran Anastasovski/Caters News)

The seven-year-old moggy has even been nicknamed Heisenpurrg - a reference to the Breaking Bad character Heisenberg who also sports a goatee. Owner Charlene Dahilig has owned Gary since he was three-weeks-old and he wandered into her backyard in Sacramento, California.