Shinobu is just an average schoolgirl and most certainly not a ninja—at least, that is what she claims. Class representative Hitoyoshi Kageyama finds this hard to believe though, as he is the only person to regularly see her scaling walls, throwing shuriken, lobbing smoke bombs, and disappearing without a trace.

Despite being an expert at combat and infiltration, Shinobu is completely inexperienced when it comes to friendship and romance. She accordingly struggles with expressing her feelings to Hitoyoshi, who is unfortunately also quite dense. Still, the two of them gradually grow closer to each other through various interactions and school activities. In the process, Shinobu also experiences life as a normal high-schooler.