Tendou Arisu 天童アリス - Battle/Armed/Bodysuit (Blue Archive ブルーアーカイブ)

ah yes, she becomes the metal gear

Tag dump:

ArisuBattle, absurdly long hair, blue eyes, black hair, hair between eyes, twintails, halo, black thighhighs, black gloves, mecha musume, leotard, bangs, blue necktie, bare shoulders,  elbow gloves, headgear,  covered navel, black skirt,  mechanical wings, detached sleeves,