Mika Ahonen (ミカ・アホネン Mika Ahonen) is a veteran Witch originating from Suomus and originally attached with the Suomus Air Force (mechanized air infantry). She is the commanding officer of the 1st Squadron from the Suomus Air Force. Although she is not a member of the 507th Joint Fighter Wing, she worked with the Suomus Misfit Squadron a lot of times. She is nicknamed 'Sister', 'Big sis' or 'Oneesama (おねえさま)' by her subordinates.
An arrogant character, Mika views the Misfit Squadron with contempt. Her first appearance in the novels has her berate nearly all of them for their past endeavors (Katharine's destruction, Elizabeth's military record, and Ursula's failed experiments).
She has a penchant for cute girls, and doesn't miss an opportunity to "touch" Haruka. This makes her subordinates (presumably all cute girls themselves) quite jealous. Because of this Tomoko labels her as a pervert.
She has a very distinct "Ohohohoho" laugh.
- Mika Ahonen is among the first witches in the series to be confirmed as an open Lesbian, with the second being Waltrud Krupinski of the 502nd Joint Fighter Wing.
- She is noted on a few occasions as treating the girls in her unit as something of a personal harem, and has made very overt romantic and sexual advances towards Haruka, of which such advances are of highly dubious consent, if even that.
- Has a male name.
- Her archetype, or if she possesses one at all, is unknown. However, there are some candidates: Leo Ahola, who has one victory, Leo Ahokas who has twelve victories or even the Finnish ski jumper Janne Ahonen. For her first name, Mika, the ex-F1 pilot Mika Häkkinen is a candidate.
- Her familiar is unknown.