When you go into someones room, with or without them there and trash it by turning things such as bags, bins, draws and upside down and generally messing things up and then leaving them the turmoil to clean up. It is usually committed as a joke as opposed to a harmful act.
"Oh my goodness, look at this mess!"
"I know, I got room raped"
Man returns to find his room in a complete mess
"Ahh shit! I've been room raped!"
"Lets go room rape James!"