I also like 'Kaz Brekker's Unlikely Ally'. In this fanfic, the reader character has a special skill that Kaz needs for his next big plan. The story is well - written, with detailed descriptions of the world of the Crows. It shows the slow - burning relationship between Kaz and the reader, starting from distrust to something more meaningful.
One great 'kaz brekker x reader fanfic' is 'The Crows and the Reader's Adventure'. It has an engaging plot where the reader character is involved in Kaz's heists, and their relationship develops in a really interesting way.
A popular one is 'In the Shadows with Kaz'. This fanfic delves deep into Kaz's complex personality and how the reader character gradually breaks through his tough exterior. It's full of great dialogue and tense moments. For example, there are scenes where the reader has to prove their loyalty to Kaz and the Crows, which makes for a very exciting read.