OVA
Description
Driven by severe financial debts, Yaeko Yanasegawa joined the Annex I mission to Mars. Raised by a single mother, she endured persistent economic hardship throughout childhood and education, unable to access popular items or social activities. She pursued academic excellence aspiring to become a nurse like her mother, but her situation worsened when caught lying about her age during part-time work, leading to school rejection. Further decline occurred after guaranteeing debt for a man posing as her father, culminating in Annex I recruitment.

Assigned to Nippon-Alliance Squad 2 under Officer Michelle K. Davis, Yaeko observed Mars’s terraformed landscape upon arrival. Contrasting it with 20th-century satellite imagery, she remarked Mars would have remained "a beautiful star" without human intervention. After combat involving Squads 1 and 2, she approached Alex K. Stewart mourning at Sheila Levitt’s grave. Voicing concern over his prolonged absence from the H.S.E.V., she consoled him by acknowledging Sheila’s virtues while rationalizing her death as unavoidable.

Yaeko framed Alex’s grief through his role as an older brother figure to Sheila and Marcos E. Garcia. She emphasized squad support from Michelle, Shokichi Komachi, and Akari Hizamaru, pledging personal protection and advocating emotional release through tears. Offering an "older sister" hug, she initially requested 5,000 yen, reducing it to 4,000 yen upon confirming Alex’s age of 18. Her claim of being 20 shocked Alex, escalating tension when he questioned her age "as a human."

Later commanding Squad 2’s H.S.E.V., Yaeko feigned defection to Squad 3, requesting missile strikes on Michelle and Akari’s position while pleading for her life. Alex sabotaged the missile—rendering it harmless—and provided Akari a katana. After battles immobilized Michelle and Akari, Bao Zhilan exploited the chaos, injuring Alex and seizing the vehicle.

Yaeko’s M.O. Operation imparted striped skunk biology, granting two anal glands that spray a butyl-mercaptan fluid causing skin/mucous-membrane irritation, temporary blindness, lung damage, and high flammability. Its extreme stench—resembling garbage and rotten eggs—measures 16,000 times stronger than surströmming and repelled Terraformars. Her low M.A.R.S. rank (#98) and biological limits indicated minimal fluid production, ranking her among Annex I’s least combat-capable members.

Additional traits include childhood anxiety over her palm’s vanished "marriage line" at age 10, an elongated tongue enabling nose-licking, and medication-administering neck patches resembling nicotine patches.