Originally Posted by
MantaLady 
If his name isn't on the lease you should be able to go to the police and ask for him to be removed as by definition he is trespassing if you have not agreed he can be there. Then give him 48 hours to come an collect his stuff at an agreed time and day which the police can also attend at the same time. Depends what country you are in though on what rights you have?
Also as you are the only one on the rental agreement you can ask your landlord to change the locks. If the BF turns up and causes any trouble you can call the police.
In the US, that would not be the case: in many states - if not all - he would have to be legally evicted since he has residency; and that internet bill is sufficient to prove residency. She can find Landlord Tenant rights online on the official government website for her area, though.
I agree with SparkleKitty - he may not know that. It just sounds like someone who says, "I'll make it difficult," may have had previous experience with this.
I won't even give anyone a key to my place, that's enough to establish residency in my state (along with that internet bill, I'd have to have a legal eviction done - which can take up to a year in my state. Unfortunately I had to do this once.)