There goes Watagiri-sensei again with the memeable faces.
You may not be satisfied with the ending, but I see a lot of potential for sequels. Even if the MC's not in denial, she could slowly develop feelings for Kasumi in a healthy pace. The fact that she's considering it to be interesting shows that she's not exactly against it, at the very least. And I'm fairly sure that p12 was still IRL, so Kasumi is more than likely gay for someone, and considers it a one-sided love (and given the MC's denial, she's likely right). So the ultimate plot twist here potentially is that it was the IRL Sora who was in a one-sided love with the IRL Benito the whole time.
So all we need now, as others also mentioned, is a sequel from Kasumi's viewpoint.