Sex with me is a night you'll never forget. That's usually how rape goes.
Why do you think it's funny? Have you raped someone in the past?
Let us say I do not believe you that it is "offensive". I think rape is funny because that's something I learned from my own experience and it was a funny experience for me.
I do think you are joking when you say rape, and I do feel like you're just being edgy with your joke, but it is hardly the right place or hardly the right time to ever joke about sexual assault specially with a lot of women are now speaking up about their experiences over the matter. I would suggest that if you in fact have assaulted someone in the past is that you make some reparations such as paying for their counselling or probably treating your future sexual partners with respect.