|This article is about a character in Umineko no Naku Koro ni.|
Although Asumu didn't have a sprite in the original sound novels and its remakes, she was given an appearance in the manga through flashbacks from other characters. She seemed to have light-colored curly hair and big eyes. She appears to be fairly tall as she and Kyrie have approximately the same height. Asumu also wore a necklace and a dress.
To Battler and Rudolf, Asumu was overall a kind individual; Rudolf especially wanted to protect her because she accepted him for who he was despite his flaws and would forgive his mistakes. However, Kyrie's perception towards Asumu is almost the complete opposite. According to Kyrie, Asumu was just one of the girls who went after Rudolf during his days as a playboy. However, unlike most girls, she was a very sly individual that was able to stir up an instinct within Rudolf to protect her. She was also noted to be quite smart by both Rudolf and Kyrie as well, having an interest in riddles.
Asumu is said by Kyrie to have butted in on her relationship with Rudolf and forced him to marry her. Both women became pregnant around the same time and Kyrie had hoped to shock Asumu with the news, but Kyrie wound up having a stillbirth while Asumu gave birth to Battler. Twilight of the Golden Witch reveals that Rudolf had bribed a doctor to switch the results; Kyrie was actually the one to give birth to Battler while Asumu had a stillbirth.
Upon her death, Rudolf immediately remarried with Kyrie, leading Battler to believe that Rudolf had betrayed Asumu and cut his ties to the Ushiromiya family for the next six years. While she is frequently vilified by Kyrie, it is hinted that Asumu was vastly different from how she is described, being a far more gentle woman who was capable of soothing Rudolf's pain, and that he married her not just out of obligation but out of love.
- Rudolf Ushiromiya (widower)
- Battler Ushiromiya (son, stepson)
- Kyrie Ushiromiya (rival)
- Piece (witch form, alternate self)
Although Asumu never appears directly in the story, she is mentioned frequently in the game's dialogue and TIPS.
Beatrice gives Battler a test and asks him to remember his sin, which he is unable to do. Beatrice then asks Battler to repeat several things in red, soon revealing that Asumu is not actually his biological mother.
Rudolf reveals to Kyrie that on the day Asumu and Kyrie were supposed to give birth, Kyrie had actually given birth to Battler while Asumu had a stillbirth. Rudolf had bribed the doctors to switch the results because he didn't want it to be known that he had an illegitimate child.
Piece is revealed to be Asumu, representing an alternate version of her who didn't die and became a recognized member of the Ushiromiya family.
If Asumu lived, she would realize the true purpose of the epitaph and help Battler and Shannon solve it. After discovering the gold, it would be given to all of the siblings and solve their money problems. Battler wouldn't forget his promise to Shannon, and they would live happily as classmates. However, Rudolf's affair with Kyrie still happens, and Ange becomes the resulting illegitimate child; Kyrie would remain as Kyrie Sumadera and Ange would take on the Sumadera surname.
- The name Asumu means "tomorrow" (明日) (asu) and "dream, vision" (夢) (mu).
- According to one of Ryukishi07's Twitter posts, he suggests that Asumu's maiden name is Akinaka. Akinaka (八月十五日) can be read as August 15.