MARRIAGETOXIN Ties the Knot on New Visuals, First Trailer and Cast Announcements

LOS ANGELES, Dec. 16, 2025 /PRNewswire/ -- Today, the MARRIAGETOXIN Project announced the release of an all-new main visual, first trailer, and additional main staff for the highly anticipated hitman x marriage swindler, battle-action series, MARRIAGETOXIN. The anime adaptation from BONES Film, known for My Hero Academia and Gachiakuta, welcomes Anna Nagase, Mariya Ise, Asaki Yuikawa, Soma Saito, Hinano Shirahama, and Simba Tsuchiya into its cast. MARRIAGETOXIN is written by Joumyaku and illustrated by Mizuki Yoda. The series is currently serialized on Shueisha's manga app Shonen Jump+ and will begin airing as a TV anime in 2026.

The newly revealed main visual offers a striking glimpse of the excitement to come, depicting protagonist and assassin Gero poised with his signature weapon, a poison needle, and marriage swindler Kinosaki holding a ring box. The first trailer features a lineup of deadly assassins who stand in the way of the strongest duo brought together by the underworld, as well as charming characters who appear throughout Gero's ultimate mission of marriage hunting. It also includes battle sequences that showcase the elite skills of Gero, a top-class assassin.

In a world swirling with conspiracies, their goal is… the perfect marriage!?
A high-stakes special mission led by the strongest duo—where poison might just conquer love—begins now!.

Say "I do" to the First Trailer: https://www.youtube.com/watch?v=s-xFia0Axr0

Assets are available here.

New Character Introductions

Kyoko Himekawa (voiced by Anna Nagase) works to recover art that has been unjustly taken and return it to its rightful owners. Highly skilled in communication, she can become friends with anyone, yet rarely speak much about herself. She has a deep love for sharks, and collects shark-themed merchandise and movies.

A businessman of the underworld, Shizuku Ushio (voiced by Mariya Ise) is a Water Master who is very thorough in her work. She completes every task with precision and is always dressed in a diving suit.

Shiori Ureshino (voiced by Asaki Yuikawa) is a college student and the heir to Balzak, a major party supply corporation worth 1.5 trillion yen. Shy and overly considerate of others' feelings, she is aware of this trait and wishes to change. Her hobby is performing magic tricks, and she loves making people smile.

Genya Naruko (voiced by Soma Saito) is the direct descendant of the Sound Master lineage who possesses a unique aura and distinctive way with words. Not only is he extremely handsome, he is highly popular among the ladies. Since he needs to stay relaxed to use his abilities, he's come up with his own unique ways to unwind.

Known as a Hamster Master, Kimie Arashiyama (voiced by Hinano Shirahama) is a branch descendant of the Beast Master bloodline. Sirius, her hamster partner, is highly skilled in intelligence work. During her childhood, she was once saved by Gero, which led her to become his secret admirer. She currently works at a small-to-medium-sized advertising agency as she is searching for her long-lost brother.

Piichi Nakagawa (voiced by Simba Tsuchiya) is an ordinary human, but a genetic anomaly with abilities far beyond a Master. He possesses exceptional information-processing skills along with superhuman physical abilities but needs to sleep over 10 hours a day to function properly. However, after sleeping, his body can heal almost any injury or ailment. In terms of pure talent as an assassin, he is among the very best in the modern era.

To celebrate the introduction of these characters in MARRIAGETOXIN, the new voice cast members share their excitement.

New Voice Cast Comments

Anna Nagase: voice of Kyoko Himekawa
"I'm Anna Nagase, and I'll be voicing Kyoko Himekawa. When I first read the original manga, I was surprised by the unexpected combination of "marriage hunting" and "hitmen," and I couldn't help but laugh at the contrast between the two themes. I'm truly thrilled to be playing Kyoko Himekawa, a character I absolutely love!"

"I was immediately drawn to Kyoko's boldness, straightforward nature, and strong inner core the moment I started reading. I can't wait for the broadcast to begin… and I hope all of you are looking forward to it as well!"

Mariya Ise: voice of Shizuku Ushio
"I'm Mariya Ise, and I will be playing Shizuku Ushio!When I first read the original manga, my reaction was, "She's wearing a helmet… and she's underwater…? How am I supposed to voice her?" (laughs). I approached the role with the hope of bringing out Ushio's coolness and mysterious aura, so I hope you enjoy my performance!"

Asaki Yuikawa: voice of Shiori Ureshino
"Because of her father's death and the enormous pressure of being the next president of a major corporation, Shiori often finds herself spiraling into negative thoughts. But at her core, she's an incredibly hard-working girl.
Thanks to her own sincerity—and the presence of Gero and the others—she grows little by little throughout the story.
Please look forward to seeing how these already charming heroines become even more wonderful as they encounter Gero and move forward together!"

Soma Saito: voice of Genya Naruko
"I'm Soma Saito, and I have the honor of voicing Genya Naruko, the 'Sound Master.'
As someone who has long enjoyed this series as a reader, being able to participate as the voice of my favorite character is truly a joy. We've already completed the recording sessions, and the atmosphere was both stimulating and wonderful—I honestly can't wait to see the finished version."

Hinano Shirahama: voice of Kimie Arashiyama
"I'm Hinano Shirahama, and I'm honored to be playing Kimie Arashiyama.

It is truly a privilege to be involved in such a fun and wonderful series!
Arashiyama is a wonderfully bold and straightforward girl who throws her whole heart into everything she does—but I also find the moments when her delicate side peeks through to be a big part of her charm.
With her expressive, ever-changing emotions, and with the unique appeal that shines all the more in a world filled with 'sound,' I approached the role with all my strength and passion—with as much energy and passion as Arashiyama herself.

Please look forward to the MARRIAGETOXIN TV anime!"

Simba Tsuchiya: voice of Piichi Nakagawa
"To me, Piichi Nakagawa is a character who embodies 'love' itself—someone who carries both kindness and madness within him. I hope to express the intense emotions flickering inside him with the same honesty and unfiltered sincerity that define Piichi."

Series Introduction
For centuries, the deadly arts have been perfected by those known as the Masters. Among them, the Poison Masters of the Five Great Families hold the most fearsome power and influence. Hikaru Gero, heir to the Poison Masters' Gero Family, has lived his entire life in the underworld, far removed from love or marriage.

But when the Gero Family head decrees that Hikaru's sister must bear an heir to preserve the bloodline – by force if necessary – Hikaru resolves to protect her at all costs. It is then that Hikaru encounters Mei Kinosaki, a brilliant marriage swindler who becomes the target of his latest job. Realizing that the only way of solving the family succession problem and protecting his sister is through marriage, Hikaru impulsively asks Mei for help in finding a bride.

"That's the first time anyone's ever proposed like that."

And so, with the cunning marriage swindler Mei as his advisor, elite assassin Hikaru embarks on the most challenging mission of his life: finding a wife!

Their goal: the ultimate marriage.

This is the world's toughest mission for love, brought to you by the ultimate duo – an assassin and a marriage swindler!

To win love, you've got to play with poison. 
A high-stakes mission for the ultimate duo begins!

STAFF:
Original Work MARRIAGETOXIN: Joumyaku・Mizuki Yoda
(Serialized in "Manga Plus by SHUEISHA"）
Director: Motonobu Hori
Series Composition & Script: Kimiko Ueno
Character Design & Chief Animation Director: Kohei Tokuoka
Sub Character Design: Yurika Sako
Costume Design: Kotono
Prop Design: Ayumi Nagaki, Ryo Hirata
Art Design: Toshiki Amata
Art: Bihou
Color Design: Hiroko Umezaki
Photography Director: Go Kanbayashi
3DCG: SANZIGEN Inc.
CG Animation Director: Taiki Nagashima
Editing: Kumiko Sakamoto
Sound Director: Haru Yamada
Sound Effects: Tomokazu Mii
Music: Taisei Iwasaki, yuma yamaguchi
Production Supervision: Bones
Animation Production: Bones Film
Production: MARRIAGETOXIN Project

CAST:
Hikaru Gero: Haruki Ishiya
Mei Kinosaki: Shion Wakayama
Kyoko Himekawa: Anna Nagase
Shizuku Ushio: Mariya Ise
Shiori Ureshino: Asaki Yuikawa
Genya Naruko: Soma Saito
Kimie Arashiyama: Hinano Shirahama
Piichi Nakagawa: Simba Tsuchiya
Akari Gero: Haruka Shiraishi
Toshiki Hanamaki: Isamu Yusen

Website: https://www.marriagetoxin-anime.com/en/
X (formerly Twitter): @marritoxi_PR
Instagram: ＠marriagetoxin_en

Copyright
Use of these images requires inclusion of the copyright notice listed below:
©Joumyaku・Mizuki Yoda/SHUEISHA, MARRIAGETOXIN Project

Original Work Information
Original Work: MARRIAGETOXIN Jyomyaku & Mizuki Yoda (Serialized in Manga Plus by SHUEISHA）
Manga Volumes 1-15 now on sale. The newest volume 16 goes on sale on January 5, 2026.

SOURCE MARRIAGETOXIN Project