She could also eat the liver of one of the girls to become immortal. After all they've been through I doubt they wouldn't at least make the offer. Maybe the creator didn't know about this detail or simply thought it wouldn't fit the story. Oh well.

HighwayMagician said:

She could also eat the liver of one of the girls to become immortal. After all they've been through I doubt they wouldn't at least make the offer. Maybe the creator didn't know about this detail or simply thought it wouldn't fit the story. Oh well.

Remilia Scarlet said:

So, how about you become immortal too, Sakuya? Then we can be together forever.

Izayoi Sakuya said:

I'll be a mortal human as long as I live, thank you. Don't worry, though. We'll be together as long as I'm alive.

Sakuya displayed her resolve to live a human life in front of Mokou and Remilia. She serves her mistress with only that one personal condition. It can be presumed that the matter of that trial of guts (IN Extra Stage) had come up at some point in the billions of years the Hourai have been together, and they had implicitly acknowledged the decision without need for additional affirmation.

It fits the canon, and therefore fits the story to not bring it up now, when Sakuya's decision to give her life to serve the last order of her dying mistress (OMG, that sounds so epic reading out loud...) is already on the table.

HighwayMagician said:

She could also eat the liver of one of the girls to become immortal. After all they've been through I doubt they wouldn't at least make the offer. Maybe the creator didn't know about this detail or simply thought it wouldn't fit the story. Oh well.

I wonder about that, as well, since, technically, they could have resolved all of this earlier by just letting themselves die if, rather than simply "making the eater immortal", eating the liver also "stole the immortality". The reason immortality is passed on is because it is "stored in the liver". That is, there's a finite quantity of it, hence the need for "three sips" to actually obtain immortality.

All Eirin would technically need to do in that case is use a little biology to create a flesh-eating bacteria that would eat their livers and consume the Hourai elixer from within them. It would create some immortal single-celled life forms, but thanks to the way in which the Hourai Elixer would prevent evolution, or even, in some strict senses of the term, reproduction, that would be far less of a problem. At the very least, everyone would be dead and nobody would care about the single-celled organisms that didn't have a consciousness to perceive eternity.