TsuMitsu

TsuMitsu is the slash ship between Yugi Tsukasa and Mitsuba Sousuke from the Toilet-bound Hanako-kun fandom.

Canon
Tsukasa and Mitsuba had their first on-camera meeting during Episode 8 of the Anime, and Chapter 19 of the Manga; but it was made clear shortly after that they had met prior to that and that Mitsuba had summoned Tsukasa to grant his vague wish of "wanting friends."

Tsukasa seemed determined to grant Mitsuba's wish, but due to the vagueness, he had to wait for someone to draw it out for him, implying he was observing Mitsuba during the whole episode/chapter. Once Mitsuba's wish was drawn out, he could begin the process of granting it. He greets Mitsuba by appearing and telling him that it "bothers him when he does these kinds of things," and then impaling his chest with his bare hand. This was later explained to be Tsukasa collecting part of his soul to create the new Mitsuba Sousuke.

In the Hell of Mirrors Arc, Tsukasa can be seen treating Mitsuba with out-of-character kindness, such as patting him on the head to console him while he was scared and crying, and supporting him and telling him how good of a job he was doing during the Mitsuba and Hanako fight. Mitsuba even clings to Tsukasa and hugs him on a few occasions during this, too.

During the Melancholy of the New No. 3, Tsukasa overhears Sakura and Natsuhiko discussing hosting a surprise party for Mitsuba, and asks them why they're saying Mitsuba is getting in the way, deliberately loud so Mitsuba can hear them. Mitsuba gets sad, and leaves the broadcasting room, prompting a, "Aww! Mitsuba ran away!" from Tsukasa. At the end of the Chapter, Tsukasa reveals that he got Mitsuba something nice; this turned out to be the 4th of the Seven Wonders, Shijima Mei.

In Chapter 12 of the Spin-Off Manga Series, After School Boy Hanako-kun, Mitsuba becomes abruptly obsessed with making friends. He tries hanging out with Tsukasa for ten minutes before he breaks it off, due to Tsukasa immediately trying to make Mitsuba swallow fireworks.

Fanon
The ship sailed likely due to the genuine kindness Tsukasa shows Mitsuba, kindness that he fails to show anyone outside of the broadcasting club, excluding Hanako. Despite this, there are still some moments where Tsukasa is emotionally and physically abusive towards Mitsuba. He punches him during the Hell of Mirrors Arc for not wanting to fight Hanako, and force-feeds him Number 3's heart in the same arc. Still in the same arc, Mitsuba flinches when Tsukasa approaches him, and begins to cry because of him. It is considered a rare pair and the ship is normally outshined by Mitsukou and Mitsunene for Mitsuba, and TsukaSaku and TsukaNene for Tsukasa. Despite this, the ship currently has 85+ works on AO3.

Fandom
FAN FICTION

Trivia

 * Tsukasa was technically the first person the remade Mitsuba ever met.

Variations

 * Broadcasting Club refers to the ship between the two, Nanamine Sakura and Hyuuga Natsuhiko
 * MitsuKouKasa refers to the ship between the two and Minamoto Kou