свой парень (свой человек) means a person(a man) of your circle.
In some case one girl can ask another: У тебя есть мальчик? - literally Do you have a boy?
More common as was said above - У тебя есть парень?
By the way will парень be translated in that case as lad?
Someone prefer to say мой молодой человек - my young man