In *Kingdom Come: Deliverance 2*, a crucial side quest involving Rosa's book is easily missed, leading to a failed quest and potentially missed romance opportunities. This guide ensures you don't miss out.
Unlocking Rosa's Book Side Quest
Before Rosa requests her book, complete "Via Argentum" and begin "Taking French Leave." After assisting the Ruthards against Vavak (through combat or diplomacy), speak with Rosa. She'll mention a secret Maleshov passage for rescuing Hans and, subsequently, ask you to retrieve her book. Inquire about the book's specifics, then agree to obtain it to initiate "Rosa's Book." This quest is only available during "Taking French Leave." Failing to retrieve the book before leaving with Hans permanently ends the quest.

Locating Rosa's Book in Maleshov
Upon entering Maleshov, Hans is in the tallest tower's top floor. Use the external stairs to access the tower. Inside, find another stairwell and a nearby kitchen. Wait in the kitchen until the guards upstairs leave.

Sneak upstairs. You'll find Lady Ofka in a room. Knock her out, then take the keys from her, the keys from the podium, and the sword from the chest. Rosa's book is a red volume in the window alcove to the right of the fireplace. Grab it; your objective will update. While there, take the sword from the chest in the adjacent room—you'll need two weapons for Hans and his guest later. Unlock the door on the left on the top floor to trigger a cutscene.

Completing the Quest
After the cutscene, continue "Taking French Leave." Guide Hans to the stables, neutralizing guards along the way. Once Hans reaches the stables, a cutscene concludes the quest. Return to Kuttenberg and deliver Rosa's book to Ruthard Palace to complete the quest. Remember, choosing the heart dialogue option here (and previously in Trosky) can advance a romance with Hans.