Otto; or, Up with Dead People (2008)

A young zombie named Otto appears on a remote highway. He has no idea where he came from or where he is going. After hitching a ride to Berlin and nesting in an abandoned amusement park, he begins to explore the city. Soon he is discovered by underground filmmaker Medea Yarn, who begins to make a documentary about him with the support of her girlfriend, Hella Bent, and her brother Adolf, who operates the camera. Meanwhile, Medea is still trying to finish Up with Dead People, the epic political-porno-zombie movie that she has been working on for years. She convinces its star, Fritz Fritze, to allow the vulnerable Otto to stay in his guest bedroom. When Otto discovers that he has a wallet that contains information about his past, before he was dead, he begins to remember details about his ex-boyfriend, Rudolf. He arranges to meet him at the schoolyard where they met, with devastating results.

Source: TMDb