Making it real is what the writer does with his characters. That is, if he wants it to feel real, having the characters leap off the pages so the reader feels as if they're in the room with him, or he's right along with them on their adventures or journeys. How do we do that?
Well, first off, with your main characters, whatever the number (I usually have six, amounting to three couples), create a different personality and characteristics for each of them. The easy way to do this is to make a characterization journal with page headings using names, or you can do it with index cards. For instance: John, Mary, Richard, Rhonda, Gerald, Louise. If you use index cards, you can have multiple cards for each character, and when you need to refer to them you just go to the index card holder and flip to the name for instant information.
Now on each page or card describe the characters: physical descriptions, favorite clothing, quirky habits, whether they are slow moving or fast, chatty or not, loud or on the quiet side, and so forth. Descriptions. The reader must be able to instantly visualize the character every time he reads his name or reads about him.
Next what are your main characters' goals and ambitions in life, in love, businesswise, and family? What do they think about? How do they express themselves? How do they behave in stressful situations, happy situations, sad, etc.? Are they highly emotional or hide their feelings?
What about their history and early life, their childhood? Were their parents loving, were they raised by one parent, or by grandparents, or on a farm, in the city? Big family, only child? Was there alcoholism, physical or sexual abuse? How were they affected if there was abuse or otherwise?
And so on.
Get to know each and every main character's heart, mind, and soul ... so the reader will be able to tap into that source through you. And the more you know the innards of your characters, you can't help but put it to paper as you are writing. Make sure you do. Share that information with your reader through the character's thoughts, dialog, and actions AND through other character's observances and interaction.
So, make it real ... regardless of the genre. Your characters must be believable in all facets.