The Ultimate Hitman and a Marriage Swindler Join Forces, Marriagetoxin Episode 1 Story & Preview Cuts Released

The story and preview images for Episode 1 of the TV anime Marriagetoxin (JP: マリッジトキシン) have been revealed. This episode will air on Tuesday, April 7 at 11:00 PM (JST), and will later be available on various international streaming platforms.

Episode 1

In the world of assassins, the "Users" stand at the absolute pinnacle. Hikaru Gero is the next head of the Gero family, a lineage of "Poison Clan" members who possess elite skills even among those specialists. Having spent his life immersed in the underworld without ever interacting with women, marriage seemed like a distant concept to him.
However, his grandmother (the current head of the family) announces that his sister, Akari, must be the one to produce an heir to prevent the Poison Clan bloodline from dying out. Determined to protect his sister from this fate, Hikaru Gero decides to get married himself. He then makes an unexpected proposal to Mei Kinosaki, a master marriage swindler he encountered as a target for assassination. Thus, the curtain rises on an unconventional matchmaking mission between a hitman and a marriage swindler.

Introduction

Hikaru Gero, a young man inheriting this deadly lineage, has lived his entire life in the underworld, far removed from the touch of romance. To him, the concept of "marriage" was a distant dream. However, to ensure the "Poison User" bloodline survives, the head of the Gero clan issues a cold ultimatum to Hikaru's sister: she will be forced to produce an heir.

Desperate to protect his sister and resolve the succession crisis, Hikaru crosses paths with his latest target—the master marriage swindler, Mei Kinosaki. In a sudden turn of events, Hikaru decides his best option is to get married himself and recruits Mei as his advisor right then and there.

"That’s a first... for a 'proposal,' anyway," Mei remarks.

And so, with a master swindler as his guide, the elite assassin Hikaru embarks on the most difficult mission of his life: Marriage Hunting. Their goal? The perfect marriage. The curtain rises on a world-class, hardcore "marriage-hunting" battle action story, featuring the ultimate buddy duo of an assassin and a con artist!

Spring 2026 Anime List

Source : Marriagetoxin Official