Well, it's hard to get her pregnant, but it prevents her from getting pregnant, However, the owner did send this to someone else, asking a similar question
You can calculate your chance to unlock it like this: (number of times you finished inside her) power of 2= %. For example:
- If you did it 8 times, it’s 8**2 = 8*8 = 64% chance
- And you can split it over 1 week too. Like:
- Day 1: 4 times
- Day 2: 4 times
- After 7 days, the total is 8 times = 64%