Fuck or quit - stress in the new flat share!

Oh man, that was an embarrassing affair. I live in a new shared flat and my flatmates don't know exactly what I do. I can't say "hey, I'm filming porn". Whenever I do a webcam, I have to make sure I'm not disturbed. Since I can't lock the room, I put a sign on the door ... Sorry We're Fucking ... or in German, bitte nicht stören. One of my flatmates didn't seem to care and just came into the room and bang, he was caught. I think he suspected it and planned the action. Because by chance he would keep the secret to himself ... for a fuck. For a fuck. Well, do I have a choice? The others really mustn't find out, otherwise I might as well move out again. I hate situations like that, but luckily men can be manipulated pretty well. I'll probably go for it but I don't know if it's wise. What do you think?