Perfect Info is a Boolean that will unlock the ability to always see if someone is pregnant or lactating even before they tell you. Otherwise it will not show in statistics until they have told you that they are pregnant/lactating.
It was intended as a debug feature but is also a way for users to circumvent the whole “slave keeping secrets” part of the mod.
Edit: The one thing to keep in mind is that the backwards compatibility formula I’ve been using really works best when checking for values within an existing dictionary in that save game. Otherwise you’ll have to add the entire new dictionary to the person class. That’s a big part of why I implemented the npcexpanded dictionary early on, as that can be an easy catch-all for any new variables added to the person class to be checked with if !person.npcexpanded.has(‘example’):