My "little brother"

So I sort of have a little brother, he's my mothers friend and sometimes in lieu of a babysitter he will come and stay with me. I like him, I don't know much about him, but he's 13 and a nice kid. Whatever. Right now it's 10:01pm and he come shuffling into my office and just sits down by the tv in my office and watches t.v. I don't know what he wants, he does this also when I am in my bedroom minding my own business. I don't know what to do or say to him, I just say hi and continue on what I am doing, he sometimes just stares at me, and its annoying cause I don't know what the hell he wants. It;s weird. I suppose I should just pipe down, he is probably bored and would much rather be at home, he has his PS2 here, and he has been watching movies, I just don't know what I am suppose to do, and I don't like him just hanging around me. Hes a sweet kid, but I guess this is just how people with siblings feel. Especially those that have 13year old brothers.