RyuSen

RyuSen is the non-binary ship between Ryuko Matoi and Senketsu from the Kill La Kill fandom.

Canon
In the series, the two meet by accident when Ryuko is looking for her father. Ryuko ends up falling down into her fathers secret laboratory, only to find her new best friend, Senketsu. Her first encounter with them is seeing, Senketsu deprived of blood, begging Ryuko to let them be worn by her. Ryuko begrudgingly agrees. Luckily for her, Senketsu gives her great powers to defeat an enemy that was seen earlier in the first episode. This here is when Senketsu decides to join Ryuko on her journey to find the person who killed her father.

During the show, it is clearly seen they care deeply for each other. As an example of this, Senketsu is quick to alert Ryuko when there is danger. Ryuko values Senketsu as a close friend she deeply trusts rather then just clothing. This is shown when Tsumugu tries to shoot down Senketsu and murder them in episode 5. However, Ryuko is quick to defend and protect them saying he will have to pry Senketsu off her dead body if he wants to hurt them.

An important thing to mention about their relationship, is when Ryuko goes through her identity crisis. During this part of the show, it is reveled that Ryuko is part Kamui. She is enraged by this, and ends up taking off and leaving Senketsu behind. Senketsu is greatly depressed about this, and ends up determined to get Ryuko back, with the help of Mako and Satsuki. When Senketsu does find Ryuko, she has been brainwashed by Nui. After a long and tiring battle, they do end up getting Ryuko back and Ryuko once again allows Senketsu to be worn by her.

Fanon
The RyuSen ship is considered a rare pair in the Kill La Kill fanbase and is quite controversial. Many fans see the ship either as a family ship, or purely platonic. There are also lots of fans who see the ship as weird, since Senketsu is not fully human, while Ryuko mostly is. The RyuSen only has around 40+ fanfics on AO3 and is beaten by other popular ships such as Ryumako. Despite the small community, lots of art have been created for the pairing. Many fans have even created human versions of Senketsu.

Fandom
FAN FICTION

Trivia

 * Ryuko named Senketsu "Senketsu" because he takes others blood,
 * Ryuko is the only one who properly cleans and irons out Senketsu. Senketsu often asks Ryuko to clean him instead of Mako's mom.
 * Senketsu has mentioned he only wants to be worn my Ryuko, and no one else. He is seen puking up blood when forced to be worn by someone else.