Cat with permanently worried eyes might break your heart

Bum the kitten may look terrified to see you, but that's just how he always looks, so don't take it personally.

Slightly cross-eyed and perpetually upset-looking, Bum was rescued by the San Diego Humane Society along with his four siblings. Immediately, they could tell something was a bit different about him:

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While he may look unhappy to be there, Bum is doing quite well and the Humane Society told Love Meow that he's really friendly with both people and other cats once you get to know him.

And he's been growing up fast:

Bum is also really bright, which has led to him exploring around a bit:

You can follow the adventures of Bum looking upset about things on his Instagram. And while Bum's been adopted, the San Diego Humane Society always has plenty more animals in need of a home.

[H/T: Love Meow]