Passionless

 is a hero personality.

Initial acquisition
During the random event Marriage Counseling, if the ruler chooses to talk to the couple, there is a 50% chance both the regent and partner acquire this personality.

Mechanics
This personality applies a persistent 50% multiplier to a hero's Fertility. This effectively does to same to his or her daily chance of conceiving a child as a regent or partner.

This effect is per hero, though, so when two Passionless heroes are married together, assuming no other Fertility modifiers, their daily chance of conception is 25% of normal for their ages.