The difference is that he was falsely accused of rape, I believe. In the young manager's case, he was basically taking advantage of his position to have sex with an employee who was desperate to keep her job. Consider this: if he let her keep her job assuming she was who she appeared to be as a result of this, the company would have to continue paying for her incompetence and there would also be the possibility of him giving into another desperate woman later. Costs like that add up, especially when it starts to affect the morale of the other employees and perhaps even cause them to put less effort into their own work. Alternatively, if he fired her all the same after doing the deed, the company still wouldn't want him because he'd have proven himself to be the sort who takes advantage of those beneath him. If you can't trust someone, you wouldn't give them management authority over other employees or company resources, right? It was a fitting end.
"Doesn't this happen in porn all the time"? Well, I'm glad he knows his Hentai situations...But in this case, unfortunately, it has backfired.
Certainly an interesting twist, though! Not sure if she's actually married, or not, but it turns out she was actually higher up in the company than he was and it was all a test, of sorts. Ah well, he may have lost his job but at least he also lost his virginity, eh?
Uh, ... best way I can express how I feel about this story is:
Twist Ending: "Omae Wa Mou Shindeiru."
Manager-kun: "Nani!?"
*Manager-kun receives termination notice*
Manager-kun (in shock) "You Must Be Joking!"
Important Life Lesson to be Learned: "Life is NOT always Just Like A Hentai or Porn Scenario - Do Your Thinking with the Head on Your Shoulders, NOT the one below your waistline."