Maho Yumeno is a second-year student at Takatoobara Middle School in Nagano Prefecture and a supporting character in the "Saki" manga. She is a former teammate of Nodoka Haramura and Yuuki Kataoka in the previous year's prefectural middle school mahjong tournament. Maho looks up to Nodoka and began playing online mahjong from her example, adopting the pseudonym "Super Mahocchi". Because she is often seen together with older teammate Hiroko Murohashi, Yuuki calls them the "Muro-Maho Combination".

In the first anime series, the Maho and Hiroko attend Nagano's prefectural high school tournament to see Nodoka's final match. In the manga, the two do not attend and are instead invited by Hisa Takei to Kiyosumi High School's national tournament training camp.

Maho has the ability to mimic other players' hands, though this is only limited to one attempt. She is able to replicate Yuuki's power play during the east wind segment of a match and has previously demonstrated plays similar to Nodoka's style. At the national tournament training camp, Maho replicates Saki's "rinshan kaihou" yaku hand. Hisa invites her to the camp in order to generate some anxiety and caution in Saki and Mako when playing an "eternal beginner".