Will her troubled past impede a young girl's efforts to become a skilled firefighter? Firefighter academy student Nanase is a sharp but relatively new fire investigator, still haunted by her parents' fiery death. Three years ago, she saved a man from a burning building. But he was no innocent victim--he turned out to be the arsonist responsible for the death of her parents. Now this serial fire-starter has started helping her solve fire-related crimes. His intentions seem good, but how can Nanase reconcile his willingness to help with his role in her own, personal tragedy? Meanwhile, another fire investigator (with his own vendetta against Firebug) becomes suspicious of Nanase and sets out to expose her relationship with the serial arsonist.