Chapter 4

Killer's Aura (殺気, Sakki) is the 4th chapter of the Parasyte manga series, written and illustrated by Hitoshi Iwaaki.

Overview
''A lion escapes from a zoo and starts mauling civilians. The lion is approached by A, and attacks him, but is quickly killed. Meanwhile Shinichi is confronted by Kotani because he also likes Satomi. Shinichi tries to refrain from fighting, but due to Kotani continuously hitting him, Migi wakes up and swiftly hits him in the face.''

Summary
In a park, a lion raised in captivity has escaped. It wanders around and kills multiple people, relishing its power over the humans that used to control it. The narration states that it would be shot once police or animal control arrived, but it only knew the pleasure of its first hunt.

A|A man shows up, unafraid of the lion. He comments on it being out of place. The lion instinctively fears him, and he says mammals are afraid of pain. An image of a large spider appears, possibly to represent his strength to the lion's instincts. He turns away, but the lion, having been captive and not experienced in trusting its instincts, sees defenseless prey and attempts to attack him. The man's face unfurls and destroys the lion's head as it leaps at him. The humans around him, unwilling to believe their eyes, tell themselves that he had an explosive.

In a basketball court Shinichi dominates the field while Satomi, along with a few other girls, cheers for him. Kotani glares and steps on Shinichi's shoes, jealous of her attention on him. As the timer runs out, Shinichi manages to throw a three-pointer singlehandedly.

Later, alone in the court he tests his hand by throwing another three-pointer from the same spot. He then tells Migi that help is unnecessary since basketball is just a game. Kotani walks up to him and mocks him for apparently talking to himself, then attempts to intimidate him to back off away from Satomi. Kotani challenges Shinichi to a fistfight and begins punching him. Trying to not wake Migi, Shinichi attempts to talk him down and block his punches with just the left hand, which only angers Kotani more.

Right before Kotani punches one last time, Shinichi yells at him to stop and he hesitates. An image of a mantis appears. Migi then lashes out and smacks Kotani harshly, knocking him over. Shinichi tells Migi to hold back, and Migi advises he check Kotani's chin for a fracture. Kotani then regains consciousness and flees, admitting defeat. Migi states that he likely didn't see anything, he just couldn't take pain.