How To Stop Intruders? Options

alright so...ive only had this problem once or twice...i guess my dreams arent that interesting but...how to stop eavesdroppers? is there a barrier you can set up while you sleep?

Ninja and Geisha are the perfect metaphorical example of entities that might attack a person while they slept since these assassins preffered to attack when query were incompassitated. The difference is that most entities that might attack you while you slept are probably parasitic and so don't want to kill you persay as rather just live off you. Again though I do believe in the possibility that there are the rare occassions where a person can encounter something that really can harm or even kill them. And I think there is little one can do to prevent such an attack unless they are already prepared - even then you never know.