In *Kingdom Come: Deliverance 2*, a crucial side quest involving Rosa's book is easily missed, leading to quest failure and potentially preventing a romance. This guide ensures you won't miss it.
Before Rosa requests the book, complete "Via Argentum" and begin "Taking French Leave." After resolving the Vavak situation with the Ruthards (through force or diplomacy), speak with Rosa to learn about a secret Maleshov passage for rescuing Hans. She'll then ask you to retrieve her book. Inquire about the book's specifics and promise to bring it to her to initiate "Rosa's Book." This quest is only available during "Taking French Leave." Failing to retrieve the book before leaving with Hans results in a failed quest and lost romance opportunity.
Upon entering Maleshov, Hans is in the tallest tower's top floor. Use the external stairs to enter. Inside, find another staircase and a small kitchen. Wait in the kitchen until the guards above leave.
Sneak upstairs to a room with Lady Ofka. Knock her out, and take the keys from her, the podium, and the chest (containing a sword). Rosa's book is in this room—a red book in the window alcove to the fireplace's right. Grab it; your objective will update.
Take the sword from the adjacent room's chest—you'll need two weapons for Hans and his guest. Unlock the left door on the top floor to trigger a cutscene.
Following the cutscene, continue "Taking French Leave." Guide Hans to the stables, neutralizing guards along the way. After the final cutscene, return to Kuttenberg City and deliver Rosa's book to her at Ruthard Palace.