The first rule of Team Seven is ‘no dying.’
Shikako and Kakashi have seventy two hours to stick to that rule.
(Or, in which Tsukuyomi isn’t torture. It’s a Trial.)
Non canonical, obviously, but basically the first thought that came to me from the title was as Orpheus and Eurydice-esque vibe. Platonic, please.
I had actually pictured it more of a literal death and Shikako, having been dead before, would be the best choice to guide Kakashi back. But I couldn’t really figure out the mechanics of how that would work or how Shikako would know it would work and as much as I think Shikako loves Kakashi (again, platonically) I don’t think she’d risk dying for such a minuscule chance to revive him when there are so many other people she loves that would be there to stop her.
If it were for Shikamaru, definitely. Naruto, she’d have to. Sasuke, probably? But with Kakashi, I don’t know… there’s a sense of… not only would other people not want Shikako to do it, but Kakashi wouldn’t want her to either? I’m pretty sure I’ve written this somewhere, but his greatest fear is putting one of his precious people in danger–him being the cause of their deaths (again)–and it’s DoS canon for the Hospital arc that he can barely accept them pulling a couple of all-nighters researching to save his life much less Shikako literally entering the death plane with much risk to her mortal soul. Or whatever deal she’d have to strike with the Shinigami or Gelel.
So literal death was out.
And then I remembered, hey, they were both in Tsukuyomi at the same time. And that’s… kiiinda like a death plane. So I figured, what if Tsukuyomi weren’t so much a set it and forget it torture genjutsu as it was an astral plane that just happened to be full of torture.
Like. Maybe Itachi just never used it on more than one person at a time? Maybe, given how much of a “pacifist” he is, torturing people mentally is something he does for a personal touch? Or not often enough to realize that there’s more to Tsukuyomi than the set it and forget it torture? I dunno.
But the point is, during their seventy two hours / one month of being in Tsukuyomi, Shikako and Kakashi basically break out of their isolated torture bubbles, find each other, and try to escape. It’s Bizarro Konoha featuring seven year old Shikako and barely-in-his-twenties Kakashi.
Maybe they stumble on the other victims of Tsukuyomi–or their shades, as such–in their own isolated torture bubbles. Including bby!Sasuke, poor child. Maybe they meet Shisui and he helps them out? MAYBE THEY MEET MIKOTO?!
I suppose it’d basically be a two person version of Lies Beyond Morning, except less head-trip-y and more run/escape the nightmare. I do like the idea of both of them being in their seven-years-ago-bodies and Kakashi having to bodily carry Shikako around because she is very small now and they are up against an army of Itachis and she cannot run very fast. Curse these short legs.
Maybe it’s a little bit of a… like when Ino went up against Orochimaru’s horcrux. Information goldmine, but at what cost. Like a leftover roadmap to Itachi’s mind (so I suppose more Inception than Kingdom Hearts), and if the two of them don’t get caught then they can uncover the truth behind the Uchiha Massacre. I mean, Shikako already knows. But this is a way for her to share what she knows with someone else. And, also, getting to the “safe” means getting out/waking up.