Lucia Konohana

Lucia is a heroine of Rewrite who is the class representative of Kotarou's class, and as such as a strong sense of responsibility and justice. She is a strong, fastidious girl who often must get involved with Kotarou's exploits when he gets out of line.

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Lucia is a member of Guardian and her abilities are a result of genetic engineering by Guardian, who wishes to create human beings capable of living in the wasteland that Earth would eventually turn into in a thousand years. A wasteland that is so harsh, that the entire atmosphere of Earth contains fatal miasma. As a result of genetic engineering that would allow her to live in this miasma, her body also produces poisonous miasma and poisonous pus. In order to subdue these poisonous excretions, she must take special medication. Another side effect of her genetic engineering is that her body creates vibrations, which she is able to direct towards foreign objects without touch. However, these inadvertent vibrations can cause trouble to machines, firearms, and other mechanisms. As a result, Lucia wields a katana in order to avoid jamming during battle (the vibrations also make her sword act like a chain-saw).

(Source: Wikipedia)