The story went from fluffy/cute to disturbing (with the revelation of Konno´s room being filled with Kanao´s photos) to cute again (when they were confessing their feelings at the hotel) to disturbing again with the revelation of Kanao´s true motives. It twisted and tossed my brain around like play putty and I loved every second of it. I need more of these stories that break tropes.
However, I do believe that the revelation of Sei also being yandere was a big stretch. The plot didn´t really set up to much information for us, except for minor acts of possessiveness towards Kanao, people avoiding Sei and the fact that we are following his inner monologue which didn´t reveal anything out the ordinary (hell, he was even wondering if it was okay for him to go in Konno´s apartment because he thought Konno and Kanao were having sex).
Like you could notice something was off the moment Kanao begins to "hang out" with Konno and doesn´t want to have public sex anymore all of a sudden, and the yandere plot twist makes sense, but not for Sei.
I will gladly recommend this story but say there´s not need to read chapters 9-11.
Public Sex