This was my virgin run (blowjobs, anal, but no vaginal sex) and I ended up at 75 Priestess Aptitude when I completed the Shrine Maiden's Pilgrimage. I don't understand why, if we are accruing Priestess Aptitude points all along for doing certain things, the game designers decided to only have that stat show up after the Pilgrimage. Why not have it be a shown stat like everything else? The way it is, we are kept ignorant of it even existing until quite late in the game.
I may do a "full slut run" (as you called it) sometime in the future.
Thanks for the offered assistance.
Okay, yeah if you are avoiding anything that can take your virginity, then I don't think you can actually get enough aptitude to become Noir's priestess, which makes sense, since part of the point of being Noir's priestess is to take semen into your own vagina so you can pass it on to Noir's. A virgin run is rather incompatible with that.
I managed a virgin run and become Noir's priestess, while even maintaining an almost clean reputation. Here are a few tips:
1) Reading explicit literature (not the very explicit version). Some of them can raise both 'exposure' and 'ass development'. And at both 50 points and 100 points, they earn you both a title and aptitude points. Both can be raised in other ways as well, but when money is no longer a real issue, this method is relative quick.
2) In the last shrine where you can also battle an avatar of Noir, I lost a few times with the help of a knock-out potion, which also gave me a title and I think some aptitude points as well, while remaining a virgin with a clean record. (you have to loose multiple times)
3) The guard at the entrance of Altoce Town enjoys 'accidentally' touch your breasts,.. which is good for chest development.
4) And a certain rope walking that people will probably recognize,.. is good for pussy development.
5) There are ways to give both head and anal (like during missionary work), that if not mistaken around 50 points also give a title and some aptitude points.