So let me see if I get what you've written straight:
Let's say there are 4 girls, each with 100% probability of showing up in "Town" (presumably for the "take a walk" option). Each girl ends up with a 25% chance of showing up, but does the overall chance of encountering any girl equal 100%, or would it be 100% of the base chance to encounter a girl?
Taken a different way, let's say there are 3 girls, each with a 25% probability of showing up in "Town." Is the chance of encountering any girl 75% (should really be 3 25% chances: ~58%) or 75% of the base chance?
What happens with a location like the slave market where more than one girl could appear at the same time? Would it populate each position as above? Let's say there are 3 slots open in the slave market and there are four girls with a 25% chance each of appearing in the slave market. Assuming the probability of any girl appearing is cumulative rather than multiplicative, the first slot would be filled, the second would have a 75% chance of being filled, and the third would have a 50% chance of being filled if the second slot was filled and a 75% chance if the second was not filled.
I'm not sure that made any sense at all. I know what I meant, but I suspect it didn't translate well into words, so I might come back and rephrase my questions later.
I'd like to see the ability to change anything and everything about the girl depending on where she is found. To extend upon your example:
<Girl Name = "Flossy Anne">
<!--
! Find her on the streets, and she has one background
!-->
<Occurrence
Place = "Town"
Chance = "15%"
Desc = "Flossy Anne barely escaped the clutches of the slavers after she was caught cheating in a high-
stakes poker game. She arrived in Crossgate after being on the run for days, on the verge of
collapse from exhaustion. She stumbled into you in the street, and in a state of near delerium,
she agreed to your terms of employment, without giving much thought to the future consequences..."
Status = "Free"
Tiredness = "100"
Health = "50"
Rebellion = "20"
/>
<!--
! Find her in the slave market, and she has another
!-->
<Occurrence
Place = "Slave Market"
Chance = "85%"
Desc = "Flossy Anne was sold into slavery after she was caught cheating in a high-stakes poker game.
She gave chase to the slavers, but was caught as she neared the city of Crossgate. She is
bitterly angry over her capture and is determined to escape at any cost..."
Status = "Slave"
Tiredness = "70"
Health = "90"
Rebellion = "60"
/>
</Girl>
[edit]
Here's a thought, it might be more intuitive if the percent chances for each occurrence are the chances that the girl appears in the game at that location as opposed to the other possible locations, rather than the percent chance that she is encountered at that location at a given moment. In the example I gave, the game would determine where Flossy Anne appears (in this case, 15% chance in Town, 85% chance in the Slave Market), and once that determination is made, she won't be found in the other location no matter what happens. You could then create conditional probabilities, like this:
<Girl Name = "Flossy Anne">
<!--
! Find her on the streets, and she has one background
!-->
<Occurrence
Place = "Town"
Chance = "15%"
Desc = "Flossy Anne barely escaped the clutches of the slavers after she was caught cheating in a high-
stakes poker game. She arrived in Crossgate after being on the run for days, on the verge of
collapse from exhaustion. She stumbled into you in the street, and in a state of near delerium,
she agreed to your terms of employment, without giving much thought to the future consequences..."
Status = "Free"
Tiredness = "100"
Health = "50"
Rebellion = "20"
/>
<!--
! Find her in the slave market, and she has another
!-->
<Occurrence
Place = "Slave Market"
Chance = "85%"
Desc = "Flossy Anne was sold into slavery after she was caught cheating in a high-stakes poker game.
She gave chase to the slavers, but was caught as she neared the city of Crossgate. She is
bitterly angry over her capture and is determined to escape at any cost..."
Condition ID = "Enslaved"
Status = "Slave"
Tiredness = "70"
Health = "90"
Rebellion = "60"
/>
<!--
! She could have been enslaved, purchased by a rival, and then obtained by the player when he raids the
! rival's brothels or defeats the rival
!-->
<Conditional occurrence
Place = "Rival's brothel"
Condition = "Enslaved"
Chance = "50%"
Desc = "Flossy Anne was sold into slavery after she was caught cheating in a high-stakes poker game.
She gave chase to the slavers, but was caught as she neared the city of Crossgate. Your rival "
+ Rival ID + " purchased her in the slave market and severely abused her in his brothel. She is
battered but not yet broken. A loving hand could raise her up and earn her eternal gratitude and
loyalty while an iron fist could break her forever..."
Tiredness = "90"
Health = "40"
Rebellion = "10"
NormalSex = "75"
Anal = "90"
Bestiality = "80"
<etc>
/>
</Girl>
Her appearances percentage chances would then be:
Town: 15%
Slave Market: 42.5%
Rival's Brothel: 42.5%
determined, say, when the .girlsx file is loaded into the game. Each play through would have a chance for her to appear somewhere else.