OttoWelt

OttoWelt is the slash ship between Otto Apocalypse and Welt Yang from the Honkai fandom.

Anti-Entropy Visual Novel
In 1955, Otto is attempting to nuke New York because Welt Joyce doesn't want to become leader of Schicksal. Welt Yang, known at the time by his birthname Joachim, accidentally snuck onto a battlefield where he witnessed Otto kill Finn, his father. Otto also attempted to kill Joachim, but Welt Joyce jumped in front of him and took the hit. This is when Welt Yang received the Herrscher of Reason core from Welt Joyce.

Manga
Second Eruption

In 1991, Welt and Einstein are on a mission to get a serum sample of Cecilia. He decides not to separate Cecilia and Siegfried, knowing from Siegfried's words that he is a good person. Otto arrives shortly after and orders Cecilia to go back to Schicksal, leaving Siegfried.

In 2000/2001, Otto sees Welt's face for the first time and finds out he isn't Joyce. Otto disguises himself to watch Sirin, Welt, and Siegfried fight. He lets Sirin escape. After this, Otto begrudgingly meets up with Welt and Einstein to discuss how to defeat Sirin. In this scene, Welt leans into Otto to whisper his plan, almost looking as if they are gonna kiss. Otto agrees to send Welt to the moon. This is despite the huge space race Schicksal and Anti-Entropy was either just or currently in at the time. Otto watches the rocket launch from Theresa's bedroom. Otto entrusted the fate of humanity to Welt's plan that had a very small chance of working.

Alien Key

In 2005, Anti-Entropy and Schicksal have a mini feud over the "Alien Key" which ends with Welt killing Ryusuke Murata.

Main Story
In 2017 [Honkai's Main Story] Anti-Entropy and Schicksal keep teaming up and becoming rivals over and over. Despite the fact Otto keeps committing atrocities, Welt's relationship with him remains a very strange friendship. In the Thus Spoke Apocalypse chapters of Honkai Impact, Otto takes every opportunity to speak with Welt that he can get. What he thought would be his last words to the Hyperion team, he tells Welt he's sorry for killing his father. In Otto's actual last words he entrusts Theresa's life to Fu Hua and Welt. He trusts Fu Hua because Fu Hua had been, for lack of a better term, by his side for centuries. But the exact reason he entrusts Welt is unknown.

Otto repeatedly calls Welt his old friend, they make their organizations fight together despite supposedly being rivals. In APHO, Welt can easily distinguish Void Archives from Otto because of how well he knew Otto.

There is a whole load of non-canon additions from Hoyoverse with Otto and Welt interactions. In the Genshin/Honkai collab, Welt mentions both previous and future meetings with Welt. They say they flatter each other, and Otto is consistently seeking Welt's approval. In the Honkai Carnival short, My Idol Debut Comedy is Wrong As I Expected, they debut as idols with Kevin. When Otto and Kevin lose their resolve, Welt inspires them, and Otto looks at him with heart eyes calling him an angel. In Dreams of Gemina, Otto and Welt are the judges, and also as judges in Stan Wars (alongside Kevin).

Honkai: Star Rail
In Luocha's companion quest, Welt is immediately suspicious of Luocha because he is a variant of Otto. Though interestingly, upon seeing his file for the first time, Welt has flashbacks about Void Archives instead of Otto.

Fanon
OttoWelt is overall not very popular, but is one of the more well-known slash ships in the fandom. VoidWelt is often mistaken as OttoWelt because of Void Archives using one of Otto's Solium bodies.

Fandom
FAN FICTION

Variations

 * LuoWelt is the ship between Welt Yang and Luocha