I'm going to throw out an unexpected prediction: the Bigger-Bad will get revealed at some point and quite possibly they will attempt assassinating Lise. I'm not sure I it will be the Childe Uncle or someone else, but I expect that either they try to assassinate Lise or when the two idiots start their War, Lise gets in the middle and tries to stop them, which might get her killed.
Perhaps, it is wishful thinking on my part (I don't want to see the Princes wind up as tragic villains), but Lise won't back down, Mil won't easily surrender, she won't let either brother kill the other or die, if she can manage, and ultimately, she's a grave threat to the Uncle and Queen.
It may turn out that the Uncle threatened the Prince & the Queen didn't know, or she later developed guilt. Either way, I don't think that Mil will get to die tragically. Lise is far more likely to jump in the middle & die stopping them, along with Michael's uncle staging the murder of Lise, which if Lise got assassinated by the Empress & House Childe, then it would mean Michael would change sides. He hasn't warned his uncle and I'm expecting him to try something when Mil is unsuccessful. I mean, his only option would be assassination or to kidnap her, which won't work, and in the end, I expect that the Uncle will prove himself the unexpected villain. Otherwise, this will have a tragic ending with either Eoise dying or something similar. As for Michael, we'll see what happens.
On a reverse harem note, it's too bad they can't just learn to be good obedient husbands to their Empress! 😂👌🏽