I actually have answered Twist/Papyrus. You can find it here:
https://itsladykit.tumblr.com/post/174500800879/wait-i-just-had-an-idea-twist-and-papyrus
As for Papyrus/Cash….
Man. Is it weird that I’ve never considered this ship?
I’ve been holding onto this ask for a while. Trying to see if something will spark…and nothing catches. I should like it, since Cash has so much in common with Razz and I love Papyrus/Razz. But….
Huh. I guess because I know that Cash would eventually do something regrettable, something to hurt Pap. And…Pap probably wouldn’t stand up for himself. I can see this being a very unhappy ship, probably ending when Pap finally has enough. Cash would be bewildered by it all. Blindsided. Unprepared.
I. I want to like it? I want to be able to see it as happy and positive…but it just isn’t working for me.
I, uh… have some feelings about this ship. I hope you don’t mind me adding them, Kit.
I feel like Papyrus would be good for Cash—but Cash wouldn’t be good for Papyrus. (With my own characterisations, at least).
Papyrus is a positive person. He’s great to be around. He tackles Cash’s insecurities, makes him feel good about himself, comforts him, gets him to open up—which is a feat in itself; Cash is a very closed off person. He doesn’t like showing affection—it feels like a weakness.
But Papyrus is similar to Cash (and any Papyrus) in that he yearns for praise and validation. He’s just more reserved about it. Better at uplifting himself.
But being with someone like Cash—someone who isn’t very supportive or affectionate—would get to him. Cash prefers to be snarky than sincere—and although Papyrus knows he doesn’t mean it… he sometimes wonders if there’s truth to it. If Cash doesn’t actually value him as much as he values Cash.
Being with Cash is bad for him, it just takes him a while to realise it, because he tries his best to see the good in everyone—even if it’s bad for his own well-being.