Tekkonkinkreet

In the old district of Treasure Town, the orphaned boys Black and White, known as the Cats, leap across rooftops and live as if the town belongs to them. A man called Snake arrives and joins with the yakuza in a plan to tear the town down and build a theme park named Kiddy Kingdom. In the fight against the assassins Snake sends after them, Black and White are separated, and Black, left alone, is swallowed by the darkness inside him.