Early in the main quest, you are tasked to go meet an officer in Paverhill. There, you are attacked by 2 soldiers. You will then be told by Trey to talk to him in the castle, which will initiate the "traitor?" quest. Once this quest is completed (find Jackie, investigate the noble quarters, talk to Trey to go to the nobles quarters at night), go to your secret bedroom, which will result in the capture of Kurohime. You will then have the quest "catgirl in training".