This is my (most likely incorrect) theory on what this animation means.
It's a futuristic post-apocalyptic world (considering we didn't see any humans or proper civilization; cities, neighborhoods, etc... Futuristic because of two reasons one being the entire human race is presumably wiped out and we see a space craft) where if you fall asleep you die.
It would explain why the girl has giant eye bags, and why she cut herself and rubbed a open lemon on the wound, it was all a desperate attempt to keep herself awake. It could also explain the green flying (fox/dog?) she has with her. It could be a futuristic genetically modified creature, or my main theory being that it is just a hallucination because of how tired she is.