UPDATE6: New information derived from fresh translations reveal the names of the new characters, and the general context of the story
--DISCLAIMER: Novellas are to be taken loosely --
Incomplete summary of events
Absconding on a trip together at Yuna's doing, Tidus and Yuna end up ship-wrecked on an ancient island where Tidus dies. Yuna is able to call him back from the Farplane after receiving help from a millennium-old unsent, but neither Tidus nor Yuna are not their old selves after this event; if Tidus realizes the way in which he was resurrected, he'll vanish, and Yuna's memories of her past life have been erased. The Farplane grows unstable afterwards, and soon the dead are being called back to Spira, including Sin.
A portion of the novella's narration is split into two alternating parts: GIRL'S SIDE, which details Tidus's and Yuna's events on the ancient island, and BOY'S SIDE, which tells the story of a female summoner and the sex-fayth method a thousand years ago. The two stories eventually merge at a point in the narrative.
Here's some new vocab you should know before you read so you won't be too confused:
Sex-fayth method - Way of creating fayth that involves establishing a mental bond with someone through sex and using that bond to create a Beast Core
Beast Core - Product of the person sacrificed through the sex-fayth method; provides the summoner the ability to use their imagination to create pyreforms based on the strength of the mental bond, instead of the preset aeons offered by the classically-created fayth
Beckoning - Act of calling the dead back from the Farplane through use of "wishing fervently" for their return[/size]GIRL'S SIDE- Tidus is resurrected and welcomed back onto Besaida. Tidus finds himself distanced upon his realization of how Spira has changed from his departure without him
b. Yuna sails herself and Tidus out to sea sans Tidus's conscientiousness; he had been asleep on the boat
c. Tidus and Yuna have sexy time on the boat because Tidus feels concupiscence, causing the boat to wreck due to absence of a helmsman- Yuna and Tidus become shipwrecked on an unknown islanda. Tidus and Yuna wander the island, trying to get their bearings straight and create a plan of action
b. Yuna, hesitant of her feelings towards Tidus, playfully yet consistently rejects his attempts at romance- Death of Tidus on unknown islanda. Tidus gets hit by a bomb in the back of his head and mistakes it for a blitzball; he approaches the bomb, which detonates and blows his head off, causing Yuna to pass out
b. Tidus vanishes into pyreflies and his body is not to be found upon Yuna's awakeningBOY'S SIDE- Story of the summoners Kushu and Ifarnal, and Kushu's guardian Briah at the ancient island during the Machina Wara. Kushu does not want to sacrifice Briah to create an aeon, and so has sex with Ifarnal to spare Briah's life
b. Kushu becomes the Beast Core for Ifarnal
c. Ifarnal turns unsent on island after he dies at 90-something
d. Ifarnal suffers through eternal life by losing the ones he loves to natural death; he had children as an unsent
e. He exists to current age, and supposedly remains on the island- Origin of Al Bhed specified GIRL'S AND BOY'S SIDEYuna encounters dead people and resurrects Tidusa. Immediately after the death of Yuna, Ifarnal speaks to Yuna and details a few things for her:
i. The revelation of the ancient island being a summoned sanction for summoners during the Machina War is revealed, as well as it's past existence as Besaid
ii. The explanation of the old way of summoning, and presumably the sex-fayth method
iii. The detailing of how reviving Tidus would entail both her loss of memory and his loss of knowledge on how he was revived; if either figure out, the process would be "undone"
iiii. The elucidation of beckoning as a way to invoke the dead back to walk amongst the livingEverybody encounters dead people and they all leave the islanda. After Tidus's resurrection, he encounters a summoned version of Kushu; she requests that he "give a woman sitting in a chair looking out of a window 'a little push' on the shoulder" (Kushu's real body located in the ruins of Besaid)
b. Ifarnal requests of Yuna that he kill the summoned version of Kushu
c. Whether or not these requests were carried out, Tidus leaves the island by method of transportation through his pyrefly-state and Yuna rides a boat provided by Ifarnal (?)---
More information will be updated with time.PAGE SCANS (two translated by site user KaminaSan and one by Pixel) IN CHRONOLOGICAL ORDER:KISS SCENE PAGE SCAN AND TRANSLATION (courtesy KaminaSan)
--- TRANSLATION ---
T: "If the sunlight gets to be too much, we'll get all red, and it's over. We also don't have the Sphere ( ) so... it'd probably just end up badly (problematic)."
Y: "Yeah, that would be a disaster, let's find some shade."
T: "I'm trying to get to the shade... but someone (
)is being un-cooperative."
Y: "Hehe...
It's not bad though..." Yuna said as she smiled and caressed her shoulders.
T: "It hurts..."
It hurts, cause I'm alive..."
T: "But we may as well confirm it with something that doesn't hurt!" Tidus said while bringing his face closer.
Yuna pulled back without thinking.
Y: "Wait..."
T: "Come on... we were spared, let's at least share the joy."
Tidus moved his pouting lips closer.
Yuna pushed away his face while laughing.
Y: "Someone could be looking! Look, for example, that orange(?), it's just like Besaid!"
You could tell Tidus lost a bit of energy.
Looking around, they checked their surroundings again.
T: "You're right... it's like the Aurochs are gonna come running from over there," Tidus said while pointing toward the entrance to the road.
Tidus/Yuna: "But something is different... something that should be here... isn't". --------
BATHING-SUIT SCENE PAGE SCAN AND TRANSLATION (courtesy KaminaSan)

--- TRANSLATION ---
The two of them held a strategy meeting in the shade of a waterfall on the road. They tried to prioritize and fully grasp the whole situation. They discussed what they would do if they met the inhabitants of this island.
T: "In any case, the first thing is to show that we mean no harm (hostility). In the case that the other party shows hostility, (can't see the kanji), and they don't understand us, RUN! If we get split up, meet back up at the waterfall entrance.
T:Well... that's the plan anyways.
Y: Sure thing!
Tidus or Yuna (not sure who): "The stone statue kind of interests me, so if you find it, check it out!"
Y: "I mean... it's not like this place should be uninhabited, right? I hope they are nice."
T: "I know, right! Although... even if they were hostile, they would probably forfeit once they got a look at you"
Y: "Huh? Why?"
T: "Come on..."
Tidus pointed to her chest, her all black bathing suit was split into upper and lower parts.
T: "I ... get excited. I tried to get used to it, but... I still get fired up even with an accidental glance."
T: "And... I sometimes think of you... THAT way. But... I want you to forgive me. I mean, I told you the truth, so you gotta forgive me!"
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TIDUS'S DEATH PAGE SCAN AND TRANSLATION (courtesy of Pixel)
--- TRANSLATION ---
"T: ""You giggled."
Y: "Its a secret."
T: "Yunaaa!"
Tidus spoke in a pitiful voice. It was funny, and unbearably adorable.
T: "Ouch!"
When she looked, Tidus was holding the back of his head.
T: "Huh?"
Tidus looked around in surprise. Before his eyes, there was a ball, rolling slowly. It was the colour of tanned leather, about the same size they use in blitzball matches.
T: "A Blitzball!?"
Tidus started walking toward the ball, looking for it's owner.
After one step...
As Yuna watched the situation, she was surprised by the tears that suddenly started welling up. Her feelings were greatly shaken, and she couldn't stand. As she crouched on the ground, holding herself with both arms, she was overcome with unbearable sadness.
Just then, there was a huge sound. Yuna was blown back by a violent explosion, thrown, spinning through the air. Something flew in front of her eyes. It was Tidus' head, fixed in an expression of surprise.
Yuna lost consciousness.
Unsent: "Remember him.
His name... was Tidus, correct?"
An unknown voice called to Yuna.
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