Monster (The Perfect Edition) Vol. 15-16 (manga)

"The key to the birth of this monster must be in my memory!" Nina remains in Prague hoping the experience will help her recall what happened in her childhood. At long last, it all comes flooding back—what happened to the young Nina and Johan? What occurred at the Red Rose Mansion? Johan never listens to anyone, never gives anyone anything. No one's desires ever interest him. What could his final goal possibly be, and what made him such a monster? As the mysterious truth is gradually revealed, what will happen next?