In *Kingdom Come: Deliverance 2*, missing certain side tasks can lead to permanent failure, and Rosa's book quest is a prime example. To ensure you don't miss out, it's crucial to know exactly where to find Rosa's book and how to complete this quest seamlessly.
Unlocking the Rosa’s Book Side Quest
To initiate the quest for Rosa's book, you must first complete the "Via Argentum" quest and then begin "Taking French Leave." During "Taking French Leave," after assisting the Ruthard family in dealing with Vavak—either through force or persuasion—you'll be directed to speak with Rosa. She'll reveal a secret passage into Maleshov that you can use to rescue Hans. In your conversation with Rosa, she'll also request that you retrieve a book for her while you're in Maleshov. Make sure to ask her about the specifics of the book and promise to bring it back to her, which officially starts the "Rosa’s Book" side quest.
This quest must be completed during "Taking French Leave." If you leave Maleshov with Hans without securing the book, the quest will fail, and you'll miss the opportunity to romance Rosa. Fortunately, the book is conveniently located along your route to Hans' room.
Upon entering Maleshov, head towards the largest tower where Hans is held at the top. Use the stairs on the side of the building to access the entrance. Once inside, you'll find another set of stairs and a kitchen nearby. Use the kitchen as a hiding spot until the guards upstairs leave the tower.

Next, carefully ascend the stairs to a room where Lady Ofka is seated, facing the fireplace. You can sneak up behind her and knock her out. Collect the keys from her body, the podium in her room, and the sword from the chest. Inside this room, to the right of the fireplace, you'll find Rosa's book in a window alcove. Pick up the red book, and your objective will update to return it to Rosa.

While in the area, don't forget to grab another sword from the chest in the adjacent room. This will save you time later when you need two weapons for Hans and his surprise guest. After securing the book and the additional sword, proceed to the top level and unlock the door on the left to trigger a cutscene.
Following the cutscene, continue with "Taking French Leave." Although Hans might not want to use the passageway, you can progress towards romancing him by choosing the heart dialogue option, provided you also chose the heart option in Trosky earlier. From here, sneak to the stables on the north side of Maleshov, dealing with guards as needed. Clear a path, signal Hans, and ensure his safe passage to the stables.
After opening the gate and finishing the quest with another cutscene, return to Kuttenberg City. Make a stop at Ruthard Palace to deliver Rosa's book, completing the "Rosa's Book" side quest in *Kingdom Come: Deliverance 2*.
