Is it normal for boys room to smell?

I have a 24yrold brother and his room smells so funky and nasty that its stinkin up the whole upstairs. I tried to open up windows and spray frebreeze but nothing is working at all. My boyfriend which is 21 bedroom smells awful too very funky I have to hold my nose when i go in there. Is this a normal thing? anyone out there experience the same thing?