I been thinking about this idea and I want someone opinion about this thought that I have in my mind:
In the "normal" ending (wedding) doesn't harry at some degree prove lucas that his way of thinking might have change thanks to harry. What I mean is that lucas didn't bailed with laura and left a sex tape on harry laptop. True, she is still getting his D, and doing horrible things to harry, but in some way laura have tied lucas to her, just like harry did to laura (even tho her emotions are clouded by lust) she still have some hidden feelings she shoved off at the back of her head towards harry. True, lucas can leave any moment he wants but he choose not to do that regardless if it is his hate boner for lucas or some secret desired for laura that is hidden in the back of his head. either way, he have been caught in harry life style without knowing, you can argue that they'll get caught by harry, but how harry is written he wil probably never find out until his kid start showing different features from him, and then he might get suspicious or probably ignored it. I'm basing this in lucas backstory. since I like to think that this might be some sort of weird game, that lucas set up in his mind, to see who is lifestyle is right, regardless of him full of his own ego thinking that his lifestyle is better. Also, if I'm not mistaken, he admitted that he would had gone for laura either way early on the game, but pure chance she was dating the guy he hated the most, so in a way harry lifestyle was better than lucas in multiple ways XD.