But you have a classroom full of students more than capable of moving the sofa to any location you desire!
As does the next teacher to use the room.
So…why is this even an issue? Do people get fired for moving a couch out of the way? Would another teacher chastise you for moving it?
Be brave. Move the couch.
Adams must have had a thing for sofas.
That would be my bet. Someone used the room and projector for a ‘movie night,’ maybe with a couple of friends and some popcorn. They probably pulled the couch in from that nook around the corner, and didn’t bother to put it back.
I’d nail it to the ceiling, along with an end table and lamp.
Attach it to the ceiling with tackle so it can be easily raised out of your way (and the swinging action would make potential unsavory use less practical).
Sofa, so good…
Right there with you, as soon as I saw the thread title!
I think you misspelled “make potentially unsavory use much more fun”. 
I recall the sofa (“chesterfield”) as being at the beginning of Life, the Universe and Everything, though my memory may be faulty. It had to do with a cricket match, a SEP (“Somebody Else’s Problem”) field and bistromathics.
Yup. And it was halfway up an entry staircase in Dirk Gently.
Possibly true. I don’t think he had a third series that he could have failed to add one to.
I’d also say he had a thing for baths and making sandwiches, especially when missing deadlines. Not that I recall any mention of either in the second series.
Perhaps the OP’s sofa is also incapable of being moved from its current position…
This. Move it and take on a “What, who me?” innocent face.
Kill it with fire.
Perhaps the sofa was put there as an accommodation to some student who has a disability that needs to elevate their feet or can’t sit at a hard desk. Don’t make assumptions.
Don’t move the sofa either. If you get some kids to do it and someone hurts themselves, you and the university will be in hot water. Also, I am sure there is some department at your university in charge of physical plant. If you start rearranging classrooms, that will surely cause a union grievance to be filed.
Look in your school directory. There must be some listing for something like physical plant, classroom services, building maintenance, or something like that. They are far more likely to know what the sofa is doing there than some random stranger on the internet. Give them a call. If someone put it there without permission, they will be glad that you told them and want to do something about it. If it is there for a reason, they can also tell you.
The creative writing teacher put there so that he could assign his students the task of writing a story about how it got there and why it is still there.
I see what you did there, Ross.
Could it be a Dire Straits song?
“Get your sofa away from me”
You don’t suppose every Sunday night at 8 (7 central), an ugly yellow family comes running in to watch TV, do you?