The premise is wild and unique—an assassin trying to become a husband with help from a marriage swindler is such a creative setup. Bones film should deliver quality animation; their track record with action sequences and character designs is consistently impressive. Assassin learning about love sounds hilarious; watching someone trained to kill navigate romance and relationships has huge comedic potential. The cast additions look solid; experienced voice actors like Mariya Ise and Soma Saito will bring depth to the supporting characters.

Following the adaptation's initial announcement in September, more info has arrived for the MARRIAGETOXIN TV anime. The latest includes the first full trailer, a brand-new visual and more cast additions. The series is scheduled to broadcast in April 2026 in Japan.

WATCH THE FIRST TRAILER: MARRIAGETOXIN TV Anime First Trailer

The visual shows Hikaru Gero with his poison needle alongside Mei Kinosaki with a ring box.

Main Cast

Hikaru Gero - Haruki Ishiya

Mei Kinosaki - Shion Wakayama

Additional Cast Members

Kyoko Himekawa - Anna Nagase (Known for: Riko Amanai in JUJUTSU KAISEN)

Shiori Ureshino - Asaki Yuikawa (Known for: Niina Shimazaki in Blue Box)

Kimie Arashiyama - Hinano Shirahama (Known for: Sara Haizaki in HOTEL INHUMANS)

Shizuku Ushio - Mariya Ise (Known for: Killua Zoldyck in Hunter x Hunter)

Genya Naruko - Soma Saito (Known for: William James Moriarty in Moriarty the Patriot)

Pilchi Nakagawa - Simba Tsuchiya (Known for: Tsutomu Goshiki in Haikyu!!)

Production Staff

Director: Motonobu Hori (Metallic Rouge)

Animation Studio: Bones film

Series Composition: Kimiko Ueno (ZENSHU)

Character Design/Chief Animation Director: Kohei Tokuoka (The Fragrant Flower Blooms With Dignity)

Music: Taisei Iwasaki (BELLE) and yuma yamaguchi (Link Click)

About the Series

The original manga by Joumyaku and Mizuki Yoda began in April 2022 on Shonen Jump+. 15 volumes are currently available in Japan, with Volume 16 scheduled for release on January 5, 2026. VIZ Media releases an English-language version.

VIZ Media Synopsis: "As a deadly assassin from the poison clan, Gero swears he'll never settle down—that is, until the family orders his sister to produce the poison clan's next heir. Refusing to let his sister abandon her chance at true love with her girlfriend, Gero desperately turns to marriage swindler Mei Kinosaki for relationship advice. Can Kinosaki turn this trained killer into a charming husband-to-be?"

Premiere Information

Date: April 2026 Location: Japan

Are you excited for this unique premise? Which new cast member are you most interested in? Do you enjoy action-comedy combinations? Will you watch when it premieres? Share your thoughts in the comments below!