Chapter 20

Signs (兆し, Kizashi) is the 20th chapter of the Parasyte manga series, written and illustrated by Hitoshi Iwaaki.

Overview
''Shinichi's father begins talking to police and gives them a description of the monsters, then later sits down with Shinichi and tells him everything about the day his mother died. The parasite formerly known as Ryoko Tamiya is seen talking to a man, where he tells her that humans are poison, and their species is the cure.''

Summary
In the evening, Shinichi enters his house and finds his father drinking alone in the dark. His father asks him when he got so strong, wondering if he's made of iron.

Later, Shinichi admits that Hideo is behaving fine in public, but Kana's ability may be a problem. He wonders if he should tell her about the parasites to keep her safe, but Migi refuses, saying that he doesn't want her knowing of him and she'll just be afraid of Shinichi too.

Shinichi is bewildered by how nobody seems to have noticed the existence of parasites, remembering the first human-host B|parasite he met as well as A. As he returns home, the new housekeeper Kawai Sumie tells him they've got company, then leaves.

Kazuyuki learns the investigators won't go public with the parasite information to avoid humans becoming scared of other humans and causing deadly mass hysteria. Shinichi enters and greets them, walking past. Takizawa, the man in charge, tells Kazuyuki that they still have no way of detecting them, and compares the situation of parasites to a few thousand wild animals loose in Japan.

Haruki Tachikawa, the police artist, interrupts to show Kazuyuki an artist rendition of the parasites and he deems it accurate. Takizawa considers the parasites' shapeshifting ability.

On a television, a talk show discusses youkai past and present, concluding with the recent Mouth-heads being seen across the country. They pull out a cartoonish artist's rendition and propose a connection between Mouth-heads and the mincemeat murders.

A man watching with the former Ryoko Tamiya scoffs at the humans, but admits that due to the widespread rumors there will be serious investigations done. Ryoko corrects him by stating the investigations are already in progress, and says she expected to be hunted down if they continue to simply kill and eat however they feel like, concluding that parasites are frail and incomplete. She then asks why they exist, and the man tells her that humans are poison and the Earth needed an antidote. She muses if that means she is raising poison inside her.

Shinichi re-enters the living room after the investigators leave, and his father demands a promise not to tell anyone what he's about to tell him, then explains the truth about his mother's death. Shinichi is already aware of all the information and more, but listens seriously and says nothing about Migi or Uda. Finally, his father tells him that his mother is dead.

In the usual subway station, Kana detects a signal again and spots Hideo. She turns away once he notices her and crashes into Mitsuo, who takes offense at Hideo's staring. Kana tries to get Mitsuo to leave, but he wants to fight Hideo, and even more so when Hideo states he was looking at Kana. Mitsuo drags him to a bathroom for a "talk" and is beat up instead while Kana leaves. Hideo then stops because he doesn't want trouble, but warns Mitsuo that the next time they fight, he'll hunt him down.