This "Non-chan" returned way before I thought, I believed she would be the "final boss" after solving the crush Taig... I mean... Juju has on Gojou, I was expecting Juju confessing before, but she got sidelined after the "Akira" arc.
Maybe Shinichi-chan doesn't know how to create conflict and she's being pressed by her editor, she even said she didn't include Gojou's parents because they would interfere with the story (two teenagers being alone with the girl being measured), she was thankful when she saw the animation and his parents were presented as dead. So in my opinion: Shinichi likes a story about cosplay, but someone else is forcing this drama, or maybe she's preparing this as a final arc and ignoring Juju's crush (poor little girl). A drama of this level can only end in both characters confessing, but at this point it looks like Gojou doesn't even know he's in love with Marin.