Multi’s “sister.” Serio is also a maid robot, designed at the same time as Multi, but by a different division of the company. She is an excellent maid. She’s very efficient, cooks well, and completes all her duties in a timely manner. However, Serio has a rather cold, unemotional, “matter-of-fact” personality. She is polite, but shows none of the heart that Multi does.

(Source: RightStuf)