I have to tell one thing here, it's not a Nepali thing, when you live with someone then you'll get to know more about the person, both good and bad things. However as a house-owner you have the right to let the tenant know what the tenant SHOULD or SHOULDN'T do while they live in your property, and it's called CONTRACT, which you do before you let that person live in your property.

About your roommate using your stuffs, you can just tell them to use their own stuffs. If you feel uneasy to confront your roommate and come here complaining like a bitch then you're the one to be blamed; that only show how pussy you are. Just because you let a Nepali live in your house doesn't mean you've done a great social service to the entire Nepali community. I'm sure you got what you wanted in return.

After reading your profile, I get a hint that you're a little control freak. You can't expect others to live like you do; DON'T drink, DON'T bring gf/bf ? Just because you are single and don't get a pussy or dick doesn't mean you make rule for others where they can't have visitor. Next time make sure you make a long contract about how your roommate SHOULD confirm to.

If you don't like Nepali roommates then put an ad in Craig's list for "CIVILIZED RACE" to live in your house.