They are not escorts. Those girls (especially the last girl) really just wanted some of that BBC that is probably rare in that area. She kept saying to him "I knew I would get you", "I told you I will get you" "And I will get you tomorrow to" to which Hakeem is not too happy about. Looks to me like she seduced him because she knows he can't resist, but I don't think his mind is in it. Even during sex she kept trying to pull him in and make eye contact but he kept avoiding it. I don't think Asia knows a thing, but yesterday she was playing Toxic by Britney Spears on repeat for about an hour and she wasn't practicing her singing, so maybe she's on to him a little...or she's under his spell too.
My theory is that Hakeem and Asia are friends with Masha and her friends, and yes it's a little random, but I think they agreed to be friends with benefits for the apartment.