Review Detail of MAOU in Assassin's Chronicle

I really really like this novel. The beginning phase were so intriguing and make me curious on what might happen... but then romance route came so early whyyyyy really why? The killing was good and everything in between compliments it all. But why susanna? The reasoning after meeting susanna became ridiculous, niya sometimes there and many times not when in fact she is included in their first party, the princess became nonexistent too like really why? The romance looks so trying hard. But I still read cause it might be good again but then I read other reviews who already finished this novel and I was at lost what should I do? So gonna read this again after lots of chapters come up.