Ugh, so sick and tired of people degrading the story and the characters.
Aristocrats don't attend parties, eat cake and get entertained 24/7 - they have to think about their social standing, their country, fiefs and dukedoms. The story's actually quite realistic in this regard. It also has a lot of mysteries but you guys just want everything served on your plate straight away. That's not how good storytelling works.
Also, the characters aren't unlikeable but realistic. Lamia's actually quite a strong girl who knows what she wants and can throw a fit.
This manhwa's 10/10. It's sad some can't appreciate that.