Shizukasa

Tsukashizu is the het ship between Tsukasa Tenma and Shizuku Hinomori from the Project SEKAI fandom.

Canon
Tsukasa and Shizuku are second-year high school students, with Tsukasa attending Kamiyama High School and Shizuku attending Miyamasuzaka Girls Academy. Tsukasa is a member of the theatre troupe Wonderlands x Showtime, and Shizuku is a part of the idol group MORE MORE JUMP! (formerly a member of Cheerful*Days). They were acquaintances in childhood, with their younger sisters Saki and Shiho being best friends. Tsukasa and Shizuku were also friends, just not as close as their siblings. They used to play in the park together.

Tsukasa and Shizuku have some parallels in their characters. They are both the oldest sibling who cares a lot and dotes on their younger sister. However only Saki unabashedly publicly cares for Tsukasa while Shiho is much more embarrassed by Shizuku's antics. They both also take up a "leader" role to some degree in their groups, with Tsukasa literally being his troupe's leader and Shizuku taking on a mentor role for Minori.

They both also tend to be the member of their group the most in the spotlight. For Tsukasa, this is naturally due to his slightly arrogant and outgoing personality, and tendency to cast himself as the lead role in all his shows. For Shizuku, this is due to her clout and fame as a former idol and model, as well as her beauty. They also tend to be forgetful, oblivious, and slightly ditzy.

Fanon
Tsukashizu is a rarepair within the Project SEKAI fandom, and there are many ships that rival it. Tsukasa and Shizuku are often shipped with all of the members from their respective units, Polyshow and Polyjump. Tsukasa and Shizuku are also individually shipped with their unit members. On Tsukasa's side, Tsukashizu is rivaled by RuiKasa, Emukasa, and Nenekasa. On Shizuku's side, Tsukashizu is rivaled by Shizuairi, Minoshizu, and Shizuharu. Although Tsukasa and Shizuku are childhood friends, they don't interact much in the game, which could be a cause for their ship's low popularity.

Tsukashizu has 5+ fan works on AO3.

Fandom
FAN FICTION

Trivia

 * Their Kizuna Rank titles include: "Friends Playing in the Park", "I'm a Firm Sister and Brother!", and "My Sister is the Cutest in the World".