In Kingdom Come: Deliverance 2, you will find an exciting side quest called "Rosa's Book". It can be completed at a certain point in the story, specifically during the "Taking French Leave" quest. Completing this quest will allow you to unlock a romantic scene with Lady Rosa. We share secrets on how to find the book for this lovely lady.
The quest is automatically activated during the storyline mission Taking French Leave. Upon arriving at the Ruthard estate, after reporting what happened at the mines, he will tell you about the underground tunnels beneath the Maleshov fortress. These secret passages were dug by Lord Ruthard himself when he owned the fortress.
Once in the fortress, you need to infiltrate the central building. Use the stairs to reach the first floor. When attempting to go higher, you will hear the guards talking with the lady. Hide under the stairs and, when they sit at the table on the first floor, proceed upstairs.
Open the door on the left and knock out the girl. You can try to intimidate her, but it will require a successful skill check. If unsuccessful, she will raise an alarm, so it's better to act stealthily.
If you are standing by the bench where the girl was sitting, on the left you will find the key to the room with the captive Ptachik. Then look to the right and take the book with the red cover from the windowsill.
It's recommended to read the book in advance, as this will help you answer Rosa's questions and increase your reputation. Upon arriving in Kuttenberg, don't forget to give the book to the girl if you plan to unlock the romantic scene with this character.
The quest doesn't end there. Rosa will be waiting for you in her room on the second floor. After examining the book, she will offer to write her own story. Agree to help her. You can choose the characters yourself. If you choose female characters, talk about Clara, Catherine, and note Rosa ("I see her clearly now!") to improve relations.
When Rosa finishes writing, read the story and return to her. Choose approving options with a moral, and the quest will be completed.