Identical "Sister(s[?])" to Misaka Mikoto of To Aru Majutsu no Index fame. Usually have blank eyes and wear a head mounted display. Whereas Mikoto has shorts on under her skirt, Misaka Imouto only wear striped panties.
Certain identifiable versions of her also have additional tags:
Misaka_Imouto_9982: she can be seen with long hair or wearing a Gekota badge on her vest
Misaka_Imouto_10032: she wears a heart-shaped necklace
Misaka_Imouto_10777: she wears a typical Russian outfit, and wields an AK pattern rifle as opposed to the F2000 issued to all the others
Misaka_Imouto_19090: unlike all other Sisters, she expresses emotions