Mizukasa

Mizutsuka is the non-binary ship between Mizuki Akiyama and Tsukasa Tenma from the Project SEKAI fandom.

Canon
Mizuki and Tsukasa are both students at Kamiyama High School, with Tsukasa being a year above Mizuki. The two met for the first time during the "Kamiyama High Festival!" event as they watched Tsukasa's play together with Akito and Touya. Mizuki found the play completely nonsensical and laughed at it throughout the whole showing. They even commented that they were tired from laughing afterward. Along with meeting during this event, Mizuki and Tsukasa also have three area conversations at school.

In one of the area conversations, Mizuki brings up that Tsukasa started aspiring to be a star to cheer up his sick younger sister, and they say that it was a really nice thing to do as a brother. Tsukasa confirms the fact but tells Mizuki that compliments won't get them anywhere with him. Mizuki then tells Tsukasa they wish they had an older brother like Tsukasa and that they're envious of Saki since she has someone so cool and dependable to rely on. Tsukasa says that he can't be Mizuki's older brother, but buying Mizuki lunch for the day is the least he could do as a dependable senpai. Mizuki excitedly thanks Tsukasa.

In another area conversation, Mizuki asks Tsukasa about the other members of Wonderlands x Showtime, specifically Emu. Tsukasa explains that Emu would raise her hand to volunteer when Rui wanted to hang Tsukasa upside down to check if the stage effects looked okay. Mizuki laughs about how hilarious the situation was. In the last area conversation Mizuki and Tsukasa have together, Mizuki asks Tsukasa what he's angry about after overhearing him grumbling about a terrible rumor. Tsukasa explains that him and Rui had been rumored to blow up the school together. Mizuki laughs and says that not even Rui would do such a messed up thing. Tsukasa rambles about how he was the one that almost got blown up, and Mizuki thinks to themself that Rui cut loose ever since meeting Tsukasa.

They later interact again in The Gentleman Thief's Thrilling White Day!? event.

In the Project SEKAI anthology, Tsukasa and Mizuki run into each other and Mizuki helps Tsukasa shop for outfits with a budget of 5000 yen. They run into Akito and Touya, and Touya comments that Tsukasa and Mizuki are an unusual pairing. Tsukasa explains that Mizuki wanted to choose his outfit no matter what, even though Mizuki didn't actually say that. Mizuki, Touya and Akito choose outfits for Tsukasa, and Tsukasa starts crying since he can't afford all the outfits everyone chose. Tsukasa buys the four of them pancakes instead.

Quotes
"Happy birthday! Your special show is just about to begin! Smile and laugh to your heart's content!"

- Tsukasa's Line for Mizuki's Birthday (2021)

Fanon
Mizutsuka is a rarepair, but it's slightly more popular in the Eastern fandom. It's overshadowed by ships like Mizuena or Mizurui on Mizuki's side AkiKasa or RuiKasa on Tsukasa's side. Polyships like Akikasamizu, Mizuenaruikasa and Mizuruikasa are sometimes used as a solution to ship everyone together. Mizutsuka has a decent amount of fanart for how small of a ship it is. The same goes for fanfiction as there are 5+ romantic Mizutsuka works and 8+ gen Mizutsuka works on AO3.

Fandom
FAN FICTION

PIXIV

TWITTER

Variations

 * Akimizukasa refers to the ship between the ship between the two and Akito Shinonome