Responses

I can think of only two reasons as to why the crown prince was gonna meet her, it's either he's there to kill her, so that the duke's weakness will be gone just like what he planned when he went to her room OR the father ask him as a favor to 1. Help her escape or 2. Have him pretend to torture her so no other would try to. I think it's the second one because he tried to stop her the moment he saw her with the knife
I think people are confused with her father's actions and esp. what really happened on the novel when she k*lled herself with a dagger. As you can see, her father really loves her. It's just that he doesn't know how to show it. Also, the fl only misunderstood him since in the novel, it was described that he never really gave her attention. But I think he was just protecting her from the emperor who was holding him by his neck through the fl (said by max). That scene where he gave her a dagger (?). The first time I read that scene I knew he wasn't telling her to kill herself. It was more like he was telling her to use that in case someone comes in to torture her. His mistake was he wasn't able to clear this misunderstanding because her daughter thought he never cared for her. The crown prince doesn't seem like the type of person to care about his family members,since he said that he has no weakness (probably except for the fl). Therefore, him saying he wanted to punish whoever tried to poison his sister was a complete lie. I think he only said that to enter the shadow room without suspicions. That's why when shr pointed the dagger to herself, he tried to stop her. The fl said the novel stopped updating after that so that means she never knew the true intentions behind his appearance in the shadow room.