It's going to be a while before I finish the next installment. I have only a vague outline of where I'm going with the story, but I thought it would be more interesting to release the individual chapters rather than wait for the whole thing. Each section that I post will be complete in itself.
Deception is a fascinating concept in fiction. I think it can be very erotic, and I've used it several times. There's a limit to how comfortable I am with it as a concept, though. At what point does deception become coercion, and seduction become rape? Deception necessarily removes a degree of consent, because you're consenting to a lie.
In the first chapter of Step-Something I have no qualms about the deception. In fact the situation is less fraught than Ethan believes - the deception makes him think what he's doing is worse than what he's comfortable with, which adds its own spice, but isn't threatening his principles or his self-image. That isn't always going to be the case, and there will be plenty more deception ahead.
Is deception a necessary part of a relationship? I can't say that it must be, but I can't think of a relationship in my own life that hasn't been deceptive in one way or another. Some have also ended due to deception, but I think most haven't.