Correct, this is about his descend into yandere mode for her.
Interesting idea.
What's at least clear is that the previous chapter had the whole color page showing her looking like a goddess or holy being from his perspective, then this chapter showing that he's subconsciously developed an emotional dependence.
But so far, it just hasn't shown him be very yandere. He's shown to be psychologically dependent on her existence, and that's clearly in line with her goal to make him want to look only at her (keikaku doori). But how he expresses that dependence could range from yandere to just... love. I mean, plenty of lovers are emotionally dependent.
Not everyone can be a yandere, or at least, not everyone is qualified to be a top-tier yandere... Just look at Kisaki's human manipulation skills and knowledge of surveillance equipment, for reference.
To me, the appeal of his character is largely related to how he's willing to risk danger to himself just to fill the hole inside himself, to make his heart race. But he hasn't been shown to be willing to do immoral things for that purpose. I'd like to see more of that inner darkness, since it's boring if everything goes exactly as Kisaki plans... But well, I don't dislike
this type of yandere, so I'll still enjoy it somewhat if the story settles for transforming his darkness into dependency. Bottom line is, I need to see more of Kisaki being crazy, rather than just the perfect girlfriend.
@fried_salad To me, it all depends on how quickly this manga wraps up. I didn't expect last chapter's development to happen so soon in the story, so now I'm afraid that it will end within a few volumes. I hope I'm wrong and it lasts for closer to 10 volumes.