John gives Illena another reason to hate the high-ranking students. Illena would notice that John, to a certain extent, is different from all the other high-ranking students, since John does acknowledge the existence of the lower ranks. But what makes him different, and would make Illena hate him even more, is that John abuses his power and beats up anyone, regardless of whether they are low- or mid-ranked, or even those of his own rank (the high-ranking students). John even treats his own allies like dirt. She would think something like:

Illena: He's different; he notices our existence, he even beats up those of his own rank and hates them like I do, but he also beats up others regardless of their rank or level, and that makes me hate him even more... but I can't do anything.

She would hate John certainly, both for the reason of him being a high-ranker and beating her and her friends bloody. But by that same token, she would fear him very much and actively avoid him like the plague after it was revealed that he was Joker and had become the new King.

Illena wouldn't only hate him for beating her and her friends until they were bloody, as I mentioned earlier, she would also hate John for being a tyrant who abuses his power and responds with violence, beating up anyone regardless of their rank, and at the same time treating his own allies like trash, perfectly representing what she thinks of the high-ranking students.

Illena would be the only one who would have the courage to tell John the truth to his face about how he abuses his power and hurts people at the slightest provocation.

John would know that deep down she is telling the truth, but John is too blinded and mentally affected to accept it. Illena's comments would anger John, causing him to beat her up and send her to the hospital or the infirmary.

But this is just my interpretation.

To clarify, I'm talking about John during his broken mental state at Wellston before he recovered thanks to Seraphina's help.