Pistol: the man of many woes.
Go to were your bed is, and yell. A good thing to yell is "fire," as the person/s sleeping will most likely always wake up and bolt for the door...... at which point you reclaim the spot that is yours. Now, before you do this, make sure you're ready to sleep..... you've taken your before bed urination trip... got a small drink... brushed your teeth.... taken your shoes off... etc.... If you do this, keep in mind that there is a possibility of being punched. But if you want your bed that bad it'll be worth it to you.