Move over Grumpy Cat: you've got some competition in the cuteness department.

Meet Bum. The little kitten has become an Internet sensation because of the permanently fixed look of worry on his face. According to the furball's Instagram page, Bum was rescued from the San Diego Humane Society Kitten Nursery.

Bum came to the shelter with four siblings where he met his human-for-life, Courtney Morman, who knew the cross-eyed cutie was special right from the start.

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"Bum is shy with new people," Morman said. "But once he knows you, he is a love bug."

Morman tells the Huffington Post that Bum was named after San Francisco Giants pitcher, Madison Bumgarner, after the team won the 2014 World Series.

The Instagram page @worried_cat_aka_bum is dedicated to Bum and his adventures. Morman hopes that others will see what a great cat he is and will decide to "adopt and not shop."