Takanashi Kiara, a phoenix who's lived through time, being reborn and revived whenever she met her end, has just revived once more (after a series of unfortunate events that has sadly, targeted her by mistake), making it her 49th revival throughout her life.
Mori Calliope, an apprentice reaper working and training directly under Death, reaping souls for many years, has seen Kiara die again. Setting off for the underworld, she prepares to meet her.
"Calli!~", Kiara runs up to the reaper enveloping her in a hug.
"Sheesh, Calli. What took so long?"
The phoenix is overjoyed at the mere sight of her best friend, who she also considers as her significant other.
"Sorry, Kusotori. Death-sensei just talked to me for a while."
Kiara looks at her with a questioning expression. "Ku so tori?"
"Wait, you don't-... Ah, right.", Calli sighs and gives a soft smile.
"That's usually what I call you, Kiara. A nickname, if you will. Anyway..." Calli stops and gives Kiara a bonk on the head.
"That's what you get. Why would you throw yourself over a cliff and then drown? You have wings! You could've just flown!"
Kiara puts on a smug smile. "Oh? Are you worried about me, Calli? You're too sweet!~"
Calli's face flushes pink. "Like I'd be! Anyway, I'm being serious here, Kusotori!"
Kiara giggles, and then faces the flustered, angry reaper. "I'm kidding. What else could I do? The person was going to fall to his death if I didn't reach for his hand on time. Also, I'm not allowed to show humans my powers, you know that."
"You could've at least asked Ina to catch you with her Takos or asked Gura to command the sea to break your fall."
"Who's Ina? And,,, Gu rah?", Kiara asks.
Calli becomes taken aback, shocked by what she has heard. But her shocked expression quickly turns to sorrow, mixed in with a hint of fear.
"looks like it got worst, just like what you've said, Death-sensei.", She says in a hushed voice.
"... Calli... Is there anything wrong?"
Kiara asks as she puts a hand over Calli's cheek.
Calli puts her hand over Kiara's and puts on a kind smile.
"Nothing... It's fine. "
Calli holds Kiara's hand and puts it down.
"Look, I'll tell you all about them later after you've revived. I'll meet you up there so wait for me."
"Sure thing, Calli!"
The phoenix does a salute, to which the reaper lets out a chuckle, and with that Calli brings Kiara back to the world of the living.
Calli lets out a deep sigh, changes into her human world outfit, and follows Kiara to the world above.
"You called for me, Death-sensei? I'm kinda on my way to meet Kusotori."
"What I'm about to tell you, concerns your significant other.", Death says calmly, but seriously.
"S-she's my, my best friend, Death-sensei."
"You know that she's revived 49 times now, right? And that this is her 50th life."
Calli nods. She holds a curious face, still wondering what her mentor has to say about her phoenix friend.
"Whenever she revives, her memory gets affected-"
"Yeah! Kusotori gets some kind of short-term amnesia when she gets revived."
"Let me finish."
Calli soon feels the uneasy atmosphere filling the office.
"That's what we know, yes, but the matter is not as simple as that." Death-sensei takes a deep breath before continuing on. "Whenever Kiara revives, fragments of her memory slowly gets erased, removed, wiped from her brain."
"But, she still remembers when we tell her about things, sensei!"
"When trying to jog her memory, her brain connects the dots and makes sense of what she's trying to remember. Her lost memories in turn, ends up being quite vague."
The moment she's heard this, Calli recalls the times when she'd tell Kiara about their moments together, and she would just reply or talk about it in a vague way.
"So what does this have to do with this being her 49th revival?"
"Since Kiara is a being that dies and becomes reborn with another life, her brain slowly alters her old memories to make way for new ones."
"So why don't we experience that?"
"We are immortal beings, we live a single life. And our minds also, technically are storing memories for one life. Kiara on the other hand, is an eternal being. She's immortal by being able to be alive again after death. Her mind is living through different lifetimes with her."
Calli feels that she does not like where this is going.
"... What I'm trying to tell you, Calliope, is that the moment Kiara dies in this 50th lifetime of hers, and gets reborn for the 50th time, she'll lose all of her memories. Every moment spent from her 1st lifetime until now will be wiped from her mind to make way for memories for her next 50 years of existence."
The sound of a dropped scythe echoes throughout the office, and this breaks Calli away from her daze.
No wonder her memory loss gets worse every time she revives. The moment she dies again, she won't remember everything. The times we all spent together, our moments with the other girls, her other friends... She won't even remember Ame, Gura, Ina... She won't even remember me.
"I-i'm sorry, sensei." Calli says, her words sounding a little agitated.
"What you've said, sensei... Does she know? Does Kiara know?"
"I'm afraid not... Do you wish to tell her?"
A part of Calli does want Kiara to know. But she's afraid it might affect the way Kiara lives her new life.
Calli stays silent for a while and tries to collect her thoughts. A few minutes later, she feels a hand on her shoulder. She looks up and sees Death-sensei right before her.
"Calliope... I told you this because as her friend, I wanted you to know. But also as her appointed reaper, I wanted you to be prepared."
Calli takes a deep breath and puts on a strong face, for now.
"I think I'll go meet her now, Death-sensei. She must've been waiting since a while ago."
Calli picks up her scythe and walks out of the office, and before she's out of earshot from Death,-sensei, she hears him tell her something.
"Don't forget my only word of advice for a reaper, Calliope."
Calli hangs her head low and fully exits from the office, away from sight.