Hogwarts: Professor Spy

(Single female protagonist, no system, no nanny) Simon Thurston, the youngest Defense Against Magic professor ever at Hogwarts His humorous teaching style is deeply loved by his classmates, and his teaching quality is also highly recognized by students. But the students don't know their professor's true face... Not only is he good at defense against the dark arts, he is also proficient in dagger fighting, the production of explosives and poisons, and specializes in eleven-millimeter revolvers. Not only can you assemble a sniper rifle in two minutes, but you can also use it to accurately snipe targets within three thousand meters. —— 1992 The dusty secret chamber slowly opens, and the lurking Death Eaters are ready to move. Dark clouds hang over the wizarding world, and the Dark Lord's resurrection is imminent The Ministry of Magic is being slaughtered, and the savior is still young. There is also a mysterious intelligence organization secretly plotting to exterminate wizards. Eavesdropping, fraud, assassination... The only person who can save the situation is an ordinary Defense Against the Dark Arts professor.