A close friend of Suou and Nika, attending the same school as them. She awakens to her latent Contractor abilities at the start of the second season, gaining the ability to summon a seemingly limitless swarm of flesh-devouring cockroaches and joining the FSB soon after. Her apparent remuneration is pulling out strands of her hair.
Spoiler: plotAs a FSB agent, she confronts Suō and Hei, demanding to know Shion's whereabouts. She battles Hei, and uses her cockroaches to devour her former boyfriend Nika, killing him almost instantly, before a surprise shot from awakened Suō knocks her out. Despite the coldness she shows towards the death of Nika, Tanya is later shown to catch glimpses of the time she and Nika spend together. She is killed after being shot by Shion Pavlichenko from afar using a PTRD-41, the same weapon manifested by Suō's contractor abilities, which has misled Hei into believing that Suou has pulled the trigger.
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