Jane Elves serves within the Anglican Church's Necessarius branch under Stiyl Magnus, operating alongside Marie Spearhead and Mallybath Blackball as a trio of witches. Initially self-taught, the trio sought Stiyl's instruction in rune magic after hitting limitations. They address him as "teacher," though primarily as mockery rather than genuine respect.

She appears as a young girl with long olive-green hair and matching eyes. Her distinctive outfit features a cat-eared hood, torso-revealing clothing, a small cape covering her neck and shoulders, and long pointed coattails. She wears black panties and stockings with an exposed garter belt, prominently displaying the Cross of St. George. Elf motifs define her core aesthetic.

Jane exhibits seriousness during missions but harbors a notable complex about her height. This surfaces during a car chase when she protests Stiyl's smoking, explicitly worrying it could stunt her growth. Stiyl dismisses this by mentioning his own sufficient growth, prompting Jane to clarify she meant herself.

Her magic specializes in wind manipulation channeled through a fan. Lacking direct offense, she provides tactical support: redirecting and amplifying allies' attacks (like boosting Marie's water spears), creating defensive barriers, enabling flight, and manipulating objects into projectiles. She possesses standard magical resistances, including defense against mind manipulation, though such attacks can still render her unconscious. Her physical capabilities are average human level, with magical attacks potentially causing wall-level destruction. She operates effectively at ranges of tens of meters.

During the Endymion incident, Jane monitored Meigo Arisa with her fellow witches. She fought Kamijou Touma and Index on an entablature, coordinating attacks with Marie and Mallybath. They retreated after Kaori Kanzaki intervened. Jane later participated in Arisa's kidnapping. During the highway pursuit by Shutaura Sequenzia and the Black Crow Unit, she assisted Stiyl in summoning Innocentius by using her wind magic alongside his rune cards, repelling most pursuers. The group was incapacitated when Shutaura overturned their vehicle. Jane rejoined Stiyl for the final mission to prevent Endymion's destruction, facing automated security and neutralizing threats. Her final appearance shows her with the hospitalized Stiyl, Marie, and Mallybath after these events.