This episode was less a resolution, unlike the previous 3 arcs we had. What we saw was more so how powerful and how creepy Usui is. Kaoruko god to think the blackmail and torturing of her father was all mental. I mean, on one hand, at least her father is alright, but damn Usui is just awful. It hurts even with how Miyo and her have connected.
Still, Usui can deal with low level supernatural users and non-supernatural users with ease. Hell, he was able to take out Kaoruko, which we know is not an easy feat. Though everything that happened was shown to Miyo with her dream sight ability. I don't think looking into the future was something she was aware of. Hopefully, Miyo uses this experience so she can communicate to Kiyoka next time. The fact that Usui retreated without taking Miyo implies that Kiyoka is beyond his capabilities.
We know that Arata never had a fulfilling childhood. Hell, when Miyo was found, he thought he finally had a purpose. Though now with Usuba family having a new purpose, we do see Usui trying to manipulate him. Usui tries to mention that him and Arata are the same, but the difference is Arata never knew Miyo. Usui was obsessed with Sumi. While for Arata it was more so Miyo's abilities that gave him a purpose. I don't think his manipulation would work here.
Got to feel bad for Kaoruko. At least Kiyoka and her superiors tried to get them to lower the punishment as much as possible. At least through all this, the friendship between Miyo and Kaoruko isn't broken. It is really nice to see Miyo be a source of inspiration for someone else. I love how Kiyoka got Karouko to say farewell to Miyo before she left. He is an immensely kind person.