It makes sense for the prince to suspect that since he didn't know about the truth. Considering all the politics around his engagement to the fake Han Sangyul, it would make sense for him to assume there are other parties with different interests. It's especially suspicious when the real is disguised and a fake is put in place. For someone who knows nothing it makes sense to assume the real Han Sangyul has a different motive too.











Guys, stop. I think it's not a redemption arc for Lari but for Khaol. He wants to safe someone now, but for the first time it's not for his sake like he did with saving Kaveri just because he wanted to be together with him again. He wanted to safe Lari for Lari's own sake and that's where the author is going.
It's not to develop Lari's character but Khaol's. Stop fucking complaining and think about it before you do.