User blog comment:IamJakuhoRaikoben/Chapter 508: Pleasure and Agony, Review./@comment-5303512-20161031161120/@comment-7418318-20161102084331

How the hell did you jump to something gross?

10 years is more than enough to fall in love with someone, do it at least once and then split up or have something happen to the lover.

For all we know her first time ended up killing her partner, but it appeared to be a natural cause in the heights of pleasure and Mavis never realized that it was actually the curse (which she didn't know she had at that point).