Hikawa

Hikawa (樋川) was one of the parasites who were responsible for the deaths of Shirou Kuramori's wife and their daughter. Along with Kusano and Maesawa, she suspected that Reiko Tamura was a traitor and tried to kill her.

Appearance
As with all other parasites, it can be assumed that Hikawa had the appearance of a slender, green, worm-like creature before she assimilated her host body.

Hikawa's host body was that of a slender fair-skinned young woman of average height and build with long brown hair and brown eyes to match.

She was seen wearing a light purple sweater and skirt.

In the anime, her face is more elongated than it is in the manga, which appears to have sharper facial features.

Personality
Hikawa believed that Reiko Tamura to be a threat and had no qualms with killing her. She remained calm and almost aloof when one of her allies was killed in front of her, but then became frantic when her own life was in danger and enraged when her own ally killed her.

Like most parasites she is dismissive of humans, assuming that they were of little consequence and the parasites could simply kill anyone in their way.

Plot
In the anime Hikawa was first seen during a parasite meeting where they discuss Shinichi and the parasite that had killed Kana Kimishima.

Later, after Shinichi kills a parasite in one of their restaurants, a meeting is held where they decide how to handle the situation. Eventually, they come to the conclusion to kill him. Miki volunteers to deal with him, though the others are slightly skeptical of his chance of success. The evening before Miki goes to hunt down Shinichi, she and Kusano burn down Kuramori's office. Kusano then sends her alone to take care of Kuramori himself, and she kills his wife and daughter in an attempt to wipe him out.

Upon realizing that they failed to actually take out the detective, Kusano and Hikawa hold a meeting with Reiko, with Kusano blaming her for everything that's happened after she praises his capacity for anger. In return, Reiko tells them she never expected them to fail so miserably at killing Kuramori. Hikawa dismissively answers that they can just kill anyone in their way. Reiko then warns them not to underestimate the human race and explains that the true power of the human species is their sheer number. However, because her way of thinking is so unusual, Kusano later decides she is a threat and must be killed.

Kusano, Maesawa and herself confront Reiko late one night, later one night, emitting strong signals of animosity that lures Reiko to their position. She confronts them head-on and has a short discussion with them, then flees. Hikawa fell behind and only arrived to the scene after part of Reiko entered Maesawa's body, while the remaining portion of her fled the battle. Hikawa stared at Maesawa as his body was destroyed, becoming frantic once he jumped on top of her. Reiko's portion inside Maesawa soon exploded from his stomach, killing him, and entered her body. She tried to fight it off, but was attacked by Kusano, who claimed that he couldn't be sure Hikawa was still in control since she was approaching him. After a quick battle and Hikawa begging for her life, her body was dismembered.

Due to the rage of being betrayed, the cut-up parts of her parasite body emitted enough killing intent to mask Reiko's approach and subsequent attack on Kusano.

Abilities & Powers
Being a "full body" parasite, Hikawa can shapeshift her head and harden her parasite cells for offensive and defensive purposes. She can detect other parasites' signals and automatically emit her own. She is able to maximize her host body's physical potential and disregard superficial damage to it.

Weaknesses
As a parasite, Hikawa requires a host body with functioning organs to survive, and would die if she were separated from her body. Fire can cause her parasite cells to "freak out", making her lose control. She is also susceptible to poisons or caustic chemicals, which would either kill her parasite cells on contact or make it more difficult for her to shapeshift her head (as seen with Hideo Shimada).

She assumed that Kusano would aid her when she was attacked, which caused both of their deaths at Reiko's hands.

Etymology

 * The surname Hikawa means "gutter, water pipe, downspout, conduit" (樋) (hi) and "river, stream" (川) (kawa).