Saikano

最終兵器彼女

In a quiet Hokkaido town, high-schoolers Shuji and Chise stumble through the awkward early days of dating, unsure how to make a clumsy relationship work. On a trip to Sapporo, an enemy air raid shatters the calm, and Shuji discovers Chise with metal wings and weaponry fused to her body: the Self-Defense Forces have remade her into Japan's ultimate weapon. As the war drags on, Chise grows ever more powerful and ever less human, with her bond to Shuji the last thread tying her to who she was.