Kiba's Long Day

Naruto draws the duty of keeping an eye on Akamaru, Kiba's nin-dog, who has been behaving oddly ever since a mission left him infected by a rare bacteria. The fear proves real when Akamaru turns on Konoha's residents in a rampage. The Anbu seize him and stand ready to put him down should no cure be found.

Unwilling to accept that outcome, Kiba springs Akamaru loose and sets out to treat him himself. Naruto gives chase, but Kiba refuses to believe the offered help is genuine. Kiba's sister Hana then shows up, and together with Naruto they move to pin down a now giant, enraged Akamaru long enough to deliver a cure from Konoha's medical team, one that carries only a fifty percent chance of working. Kiba pulls it off and nearly dies doing so. It later comes out that Akamaru had strained to avoid every vital point on him, a mercy Kiba later thanks him for.

This original-series filler also circulates under the name the Akamaru Monitoring Mission. It leans hard on the bond between Kiba and his partner, framing the whole ordeal around loyalty tested to the edge of death.