Yuki Yuna is a Hero: Washio Sumi's Chapter - Promise (結城友奈は勇者である: 鷲尾すみの章 - 約束 Yuki Yuna wa Yuusha De Aru: Washio Sumi no Sho - Yakusoku) is the third film of a trilogy surrounding Washio Sumi is a Hero. It aired on July 8th, 2017.

Screen Shot 2017-07-18 at 6.11.52 PM
Chief Animation Director Sakai Takahiro
Japanese Air Date

July 8th, 2017

Opening Sakiwafu Hana
Ending Yakusoku
Previous Next
Soul N/A →

Summary Edit

A rainstorm falls over the city as the class weeps over Minowa Gin's death. During her funeral, Sumi and Sonoko give her flowers to remember her by, when Gin's younger brother Tetsuo breaks down and screams at the Shinju for letting this happen. Just when a Taisha member is about to sit, time stops. Sumi, in rage because of the timing and the fact, screams as she runs into battle, defeating the monster in mere minutes. The two are praised by Aki-sensei for doing their job, but is asked by Sonoko she remember Gin. In class, the two girls are bombarding with uneasy questions about their 'duty', and Aki-sensei gives them a day off. The girls spend it at a festival, shooting for prizes, eating food, honoring Gin with a small lucky cat and becoming closer as friends. Then during a training session, the newest system update is announced. The girls go through a special ritual, and are introduced to their fairies. Sumi starts to move on from Gin's death, happy her family is alive and well. Their classmates have realized the true weight of the girls' duty-so they make a banner as an apology gift, which they graciously accept. Sonoko then drags Sumi to a Halloween store so the two can celebrate "The Pumpkin Festival". The cloudcuckoolander reveals her fairy is nicknamed Sebastian, and he causes a little mischief. Meanwhile, Aki-sensei informs the parents on the system updates...and they are not happy. Sumi and Sonoko glide down a road together, when time stops and their phones blare with a message: "Forestize Warning". Eager to test out their new equipment, the remaining heroes step into battle only to find 3 Vertexes. Knowing Gin had soloed 3, they quickly transform to fight. Sumi names her new rifle 'Shirogane' after Gin. Not long after they begin fighting do the girls witness their fails protecting them and experience Mankai for the first time. With increased firepower, Sumi destroys a core by accident, watching the lights go up in confusion. The effect wears off, and Sumi finds she can no longer walk and Sonoko lost an eye. Focusing on the battle, they are forced to go Mankai again. Sonoko's arm goes numb, and she starts to piece the puzzle together, yet Sumi grows fatigued and asks Sonoko to take care of the last Vertex. She says she will, goes Mankai, and destroys the Vertex far enough the Soul is visible. It floats through a barrier, and Sonoko starts to follow, when she gets a feeling like her 'heart stopped suddenly'. She walks out and sees the world's true state, Vertexes regenerating quick then ever, in fear and terror. She puts a hand on her chest to calm down, then notices her heart is suddenly silent. She then says " that's how it is." and goes back to warn Sumi. Sumi doesn't recognize her, and asks where Gin is. Dawning on Sonoko that Sumi is losing her memories, she screams her friend's name, then tells her about the 3 of them while gently timing the ribbon around her arm. An army of 20 Vertexes appear, and Sonoko goes off to fight. Knowing she won't die, she isn't scared. Sumi suddenly wakes up in a hospital room, not knowing her name, and admires the strange ribbon on her wrist. Confined to a wheelchair, the girl sees her new house and wonders about her family's wealth. A voice interrupts her, and a girl with red hair and a big smile introduces herself as Yuki Yuna. The amnesiac smiles and takes her hand in greeting, saying "I'm...Togo Mimori."

Character Appearances Edit

By order of appearances:


Washio Sumi

Nogi Sonoko

Minowa Gin (body)

Minowa Tetsuo

Minowa Kintarou

Togo Mimori

Yuki Yuna

Trivia Edit

Navigation Edit

Episodes of "Yuki Yuna is a Hero" Anime Series
FriendsSpiritPromiseA Maiden's True HeartNoble ThoughtsMoral PoiseShining HeartsOvercoming AdversityIn Anticipation of TomorrowIdyllic HappinessBlessings of the GodsThose Who Know GriefBonds of LovePassionSmile At You

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