|AKA:||"Plum" (English Manga)|
|Height:||16cm (6 Inches Approx.)|
|Volume 1, Chapter 3|
|Episode 1: Chi Awakens|
Sumomo (すもも), known as "Plum" in the Tokyopop English manga, is Shinbo's miniature "mobile persocom"—the equivalent of a laptop computer.
She is wearing an outfit that makes her resemble a genie.
She is programmed to be cute and tends to be quite hyperactive, for example, leading Hideki in wake-up exercises each morning and dancing when she is in standby mode. Shinbo was the original owner of Sumomo, but left her with Hideki after leaving with Takako. He later transfers Sumomo's registration to Hideki, giving him permanent ownership. At the beginning of the series, Shinbo uses a newly-upgraded Sumomo in an attempt to analyze Chi, and Sumomo is nearly broken in the process, requiring new main memory, and in the manga, a new video card, as well. Once Kotoko joined Hideki, she quickly came to the conclusion that Sumomo was mad, with her nonsensical ways.
- Her Japanese voice actress, Motoko Kumai, is also known for portraying Syaoran Li from Cardcaptor Sakura, Keita Yoshimura from Kobato and Nataku from X/1999; all also being CLAMP's works.
- Her Enlgish voice actress, Sandy Fox, is also known for voicing Lady Aska and Hikari from Magic Knight Rayearth, another anime adaptation of one of CLAMP's manga.