Kafka has finally made her debut in Honkai Star Rail 1.2 update as a playable character, and so will her companion quest called "Letter From A Strange Woman," which you will be able to complete to get free rewards like Stellar Jades, Trailblaze EXP, Credits, and more.
However, you will have to unlock it after completing Trailblaze Mission "Xianzhou Luofu — A Dragon Gallant, Its Ocean Distant" and then reading specific Messages. Once you have done it, here is how you can complete Kafka's companion mission in Honkai Star Rail.
Honkai Star Rail Kafka Companion Mission: How To Unlock & Complete
After you have unlocked Kafka's companion mission, Letter From A Strange Woman, you will receive a text from an Anonymous person who calls themselves Kafka and ask you to come to Divination Commission alone. You will have to talk to the person to get the coordinates, and the quest will begin.
You will then have to go to the location marked on the map and meet Kafka there. Talk to her, and she will ask for your help. You will have to either accept or reject her quest, and the outcomes of the quest will be different based on the choice you make.
We have provided a complete walkthrough for both outcomes below:
Help Kafka
After you choose "Yes, it sounded like you needed some," you will agree to help Kafka and then. you will be tasked to beat the enemies at the locations marked on the map. After that, you will have to talk to Kafka, and she will ask you to play truth and lies. You can give the answers of your choice, and the outcome will still be the same.
After you answer her first question, you will then have to fight Cloud Knights and then go back to Kafka. Talk to her, and now it's time for you to ask a question. Choose the option that you like and listen to Kafka's answer. You will then have to fight the enemies again at the locations marked on the map.
Return to Kafka and answer her next question. Then, you need to ask her your last question and fight Fight Cloud Knight Lieutenant Yanqing. After beating him, you will have to talk to Blade and Kafka to complete the Kafka Companion Mission and receive True Free Will achievement.
Refuse to Help Kafka
If you refuse to help Kafka, a series of dialogues will begin, and she will try to change your mind. However, you will have to keep refusing, and she will finally let you go. You will then get an option to leave Kafka alone or help her. Go to the point marked on the map other than Kafka and the Kafka Companion Mission will be completed and you will get True Free Will achievement.