Production I.G Short Animation: The Girl from the Other Side

Touch not the Outsiders, lest ye become an Outsider. But when two creatures belonging to opposite kinds -a lost little girl from the Inside and a demonic beast-looking Outsider- initiate an impossible coexistence on the same side of the forest, their bond seems to transcend their incompatible natures and the unnamed curse that has divided the world.
Based on Angouleme-nominated, eponymous best-selling graphic novel by manga artist Nagabe.