I'm not so sure about what Kiyoka's answer is going to be, while it's highly likely she'll say no due to how she is right now, her saying yes would be less predictable. I have not read any other story from this mangaka so I can't tell if they're the type to throw curveballs like Kiyoka becoming Shunsuke's gf while she doesn't appear to have any strong feelings for him. Y'know, like "fake relationship for the sake of gaining experience to help with writing novels." Or maybe forcing Hinaki to realize she's also in love like others pointed out.
I would personally prefer to see them get together only after Kiyoka actually falls in love with Shunsuke though. We know she doesn't like him that way (yet). Shunsuke and Kiyoka dating now would actually be a crappy deal for all 3 of them. Shunsuke is expecting to get rejected and wouldn't be happy with a fake gf, Kiyoka doesn't love him romantically and Hinaki certainly doesn't want them dating.