Natsumi is Akari's childhood friend, though their paths diverged after high school—while Akari went to university, Natsumi stayed behind to work in her family's auto repair shop. She's got red hair and a direct, no-nonsense way of talking that initially made Sorawo peg her as trouble, but that's mostly just how she is around people she doesn't know well. Akari points out that Natsumi's actually pretty similar to Sorawo in that regard—both of them are just awkward with strangers.
After Sorawo and Toriko help her deal with the Sannuki-san apparition, Natsumi returns the favor by agreeing to modify their AP-1 vehicle.
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