Yumenberg

Yumenberg is the femslash ship between Celestia Ludenberg and Yumeko Jibami from the Danganronpa and Kakegurui fandom.

Canon
Since Celestia and Yumeko are from different series, they never met in canon.

Both characters' special interest is gambling. They have no problem with lying and have questionable mental stability. They also both have black hair and red eyes. Both prefer to wear dark red and black clothing. Celeste of course picked out the outfit she wears in game, while Yumeko chooses to wear her school uniform even when she doesn't need to.

They both are also probably addicted to gambling, given Yumeko's obvious obsession with it and Celestia being an Ultimate Gambler. They are both very good at it. Celeste is described as "taking [people's] life savings and laughing while she did it," and Yumeko surprised many with her hidden skills, beating Mary in a match on her first day.

Yumeko and Celestia both smile most of the time, even if it isn't pertinent to the situation. However, when someone irritates them, they get quite sadistic and can be really mean to the person who angered them. Both girls also show a big respect to the people they find interesting.

Fanon
Some fans theorize that Yumeko could have received a different life schedule. This schedule could have said that she would attend Hope’s Peak as Celestia Ludenberg. And knowing that Yumeko would accept her fate she ended up doing so. However, it's not confirmed yet.

Yumenberg sailed as a result of both characters being fairly similar. While the two having the same colored hair and eyes makes them look like sisters. Some fanwork of the ship has the two getting together for a game, since it is one of the main traits that gets fans to ship them.

Fandom
TUMBLR

Trivia

 * Both wear black and red clothes that fit with their hair or eyes.
 * They put their lives on the line by playing games, like Russian Roulette.
 * Both characters are incredibly rich.
 * Their real names end with eko. (Celestia = Taeko ; Yumeko)
 * Celeste has a cat, Grand Bois Cheri Ludenberg, while Yumeko pretends to be a cat in an episode of Kakegurui.
 * They both wear metal accesories on their fingers. Yumeko has a ring in her left thumb and Celestia wears a Gunmetal Armour ring in her right index.
 * Celestia wears black nail polish while Yumeko wears red nail polish (sometimes seen like pink).
 * Both girls wear black long stockings.