Shani

[Hayashi.226]

When and where did Shani get acquainted with Geralt? I've just reached the outskirts of Vizima and it's readily apparent that she knows him personally.

 

[Jesting-Jack]

They meet for the first time in Blood of Elves.

Here's a short account of her dealings with Geralt during that time: Shani Biography

 

[SigilFey]

Yes, the games assume that the player is quite familiar with the novels. Chronologically, the games take place after everything Sapkowski had written at that point.

You can catch up with any number of summaries online, though I recommend actually reading the novels if you can!