Chapter 25

Ripples (波紋, Hamon) is the 25th chapter of the Parasyte manga series, written and illustrated by Hitoshi Iwaaki.

Overview
''As news begins to spread about Hideo's rampage, the police try to cover it up and say it was a teenager on drugs, while witness reports say it was a monster. People begin to become paranoid as rumors of the creatures appearing become more frequent. After studying Hideo's body, Dr. Yui comes to the conclusion of how to identify these creatures and how some of their anatomy works.''

Summary
Unknown people discuss the parasites, the eyewitness reports of Hideo Shimada and the hole in his chest.

Several reporters walk around, accosting students in hopes of more information about Hideo. One follows behind while Shinichi and Satomi check up on each other, then leaves to bother another student. The news reveals that two weeks have passed, and official statements are of a teenager berserk on steroids though eyewitnesses contradict this and state that it was a monster. Additionally, the officials refuse to make further statements and the parasite's identity has not been released to the public.

Kawai Sumie, housekeeper, is watching the report when Kazuyuki walks in. He tells her she's fine to keep watching, and she awkwardly tells him she saw Shinichi on the news. She later greets Shinichi as he comes home and tells him as well. Shinichi wonders to Migi why the officials won't release information about the parasites to the public, and Migi points out that normal humans have no way of telling them apart as well as refuses Shinichi's suggestion to help hunt and kill them. Migi then asks how Shinichi would feel if he were in Migi's place killing his own species, which causes him to go silent.

Manga narration states that it was discovered Hideo Shimada was a fake name with no prior records and no proof of him being a minor, which led to the information being widespread. A few people begin to assert that Hideo was not human. The rumors of monsters disguised as humans lead to anyone strange being ostracized or bullied, with suicides rising from paranoia of victimization or inability to trust people.

At a meeting, officials debate on whether to release information about the parasites or not. America is mentioned possibly planning to use parasites as military forces. Takizawa and Dr. Yui then enter, with Takizawa suggesting they spread rumors of how to detect parasites even if they don't confirm the existence of them. Yui begins to lecture on the biology of parasites, including their morphing abilities and capability as thinking muscles. Takizawa interrupts him as he goes indepth and completely loses the audience, requesting to know how to identify them. Yui then explains that smaller parasite pieces will attempt to reconnect to the larger mass, while pieces the size of a hair will struggle but be unable to reconnect, and fall apart as they die.

Takizawa then requests that each person allow him to pull out a hair as his bodyguard closes the door and pulls out a large gun.

A month after Hideo's death, paranoia died down while a trend of pulling out hair from old friends emerged. Kiyomi and her friend cross paths and each pull out a strand of the other's hair.