I watched it a few years ago at school on Youtube but it was like;
A bunny is a lightkeeper who keeps the darkness out of the town but is being bullied at school. He meets a friend who's an artist and is happy for once, he sees her laughing with some kids at a picture she drew and ripped it away from her to see a picture of him drawn crudely and on the top it said like Trash or smt. So he's sad, puts on a gas mask and legs the darkness overtakes the city. But while sitting on a swing set, he finds the other half of her drawing and it's of her drawn crudely too and together it read like "Trash buddies" or something similar, and he rushed to his lighthouse and fixed the darkness