Thank you for resuming this project, I'm glad to see another chapter for this manga. I didn't know the cause was that the author effectively went on hiatus leading to no raws to work with.
"Nanamori-san also told me that she and Tateyama-san were doing it for this manga's sake"
Wait, what? Since when did Yokozawa and Nanamori get in touch? I went and re-read chapter 3, and Tateyama is also wondering if he ever mentioned Nanamori to Yokozawa, which I think he did not. IIRC Yokozawa is stalking Tateyama, so maybe she somehow got in touch with her offscreen or something...?
If these two ladies were in touch behind the scenes, that brings the possibility that the events of chapter 4 have somehow been agreed upon by these two, but it got ruined by how our male lead dutifully chose work and Yokozawa-sensei. Did Yokozawa just engineer a situation that she could use as material for her work? Trying (but failing) to push Tateyama and Nanamori together so she could write about it? And maybe Nanamori agreed because she wanted to get closer to Tateyama?
Hence the line "you're so serious it's boring" - him choosing his duty as her caretaker editor was definitely not what she expected or wanted. Then again, if Tateyama and Nanamori plotted this, Nanamori's reactions do not line up with it. She seemed genuinely surprised over hearing a woman in the call and also genuinely concerned and apologetic over causing the hang up and subsequent ghosting. Whatever the case, plans went wrong there. For maybe all 3 of them.
Yokozawa-sensei is hot, but I'm pretty sure she's dangerous over how she knows too much on Tateyama. The smoking hot but expressionless assistant Gotou could be less dangerous, but alas she was missing this chapter. I don't know enough about Nanamori to say much, but she seems to be the saner (only slightly), and kinda seiso option here. Too early to tell who's best girl, but for now I'm curious about Nanamori. It felt too convenient that she suddenly asked him to meet after many years.