Airbnb Host Goes Into Our Flat Watches Us Having S*x And Refuses To Go. What To Do Now? [germany]

Hi Guys, So yeah the title basically says everything. We booked an airbnb flat in Germany where the host is living next door. We ordered some food put on a movie, had sex and totally forgot about the food. My boyfriend being balls deep into me l finally notice a face standing behind him. Our host. Idk how long he stood there. He grinned at us, told us our food is here. Of course we told him to fucking leave, he refused to, started talking about our tv being too loud and scolded us for being unable to track the food since we were having sex. (Apparently he met the delivery guy in front of the door) He stood there for at least 4 mins talking to us while we were both COMPLETLY NAKED. And REFUSED TO LEAVE. I'm so digusted at his perverted grin. This will live rent free in my head for the next months. In the community guidelines I read, that he isn't even allowed to get into the flat while it's unattended based on Airbnbs Privacy Law. What can we do now? Can we take legal action?