Enjous plan doesn't involve leaving a letter or lying to Liyu. It involves removing Lirens body, permanently, and tidying up the house. We thereby remove the event that ruins Liyus "perfect day" that allows the Kukuni to reset the day.
Apologies, I got my plans mixed but a bit there.
That being said there is at least one point I want to relitigate:
Why would the Kukuni deliberately fuck itself over?
Kukuni aren't human. A Human might decide that they'll sell out their principles for the sake of power, but a Kukuni
is it's moment. It'd be one thing if the argument was the Kukuni
cannot help Liren, but it's being argued that it's deliberately trying to sabotage the perfect day.
It's also arguing very had that the day will be perfect, MUST be perfect.... and you're saying it's leaving a great sticking turd of a corpse in its day on purpose?
I think the simpler answer is the Kukuni just cannot understand what makes Liyu care that there's a corpse in the house. Heck, it outright stated as much.
"You mortals are untidy. Messy. You contaminate the world around you with worthless thoughts and useless sentiments."
<Annoyance. Anger. Disgust.>
Mei Daiyu turns the egg in her grasp, examining it idly. "The very setting of this conversation pollutes the world. We could be speaking anywhere. A still meadow or a remote cave. In fact, there need not be a setting at all; the world around us could be empty, leaving only the things that matter."
"Yet we are here," she murmurs. "Here in a place of sentiment. Of meaning. Of mortality."
This thing is a Reddit Atheist. It wants to make a 'perfect day', but it cannot understand the Sentiments and emotions that go into making a Perfect day or moment actually perfect. Like...
Why did a village full of people lie to a child about her Father? Because they cared about her happiness. This thing would never understand that except in the abstract.
This is probably a big part of why I think the Funeral is the core part, in terms of thematics, though I don't think Perfect Day plan exactly distracts from it. It's still having the funeral after all.
Not only is a Funeral a ceremony of closure, but a funeral is PURELY sentimental. There's nothing to be gained from it in terms of raw serotonin, nothing as simple as "Catch more fish" or "All tools nice". It's a sad moment, but also a happy one.