The Spring 2026 Anime Preview Guide

MARRIAGETOXIN

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.

MARRIAGETOXIN is based on the manga series by writer Jōmyaku and artist Mizuki Yoda. The anime series is streaming on Crunchyroll on Tuesdays.

MARRIAGETOXIN is one of this season's bigger premieres, and I've been eagerly waiting to get my hands on it. It's a title that my wife absolutely adores, so I've had good reason to suspect that I'd also really dig it. However, I've also gone out of my way to avoid learning too much about the series in advance, so I didn't really know what to expect from this premiere beyond my knowledge of its basic premise. The opening sequence absolutely sells what this series is going to be all about: We get a crazy establishment of chain-smoking fat-cats sitting on an army of human slaves who live as chairs for their masters, and one man casually saunters in to brutally poison the outfit's disgusting leader—only for some underling to take the blame. Then, as our assassin coolly makes his exit onto the dark and sultry streets of the city, he is so distracted by the sight of two folks sneaking a kiss under the streetlights that he walks headfirst into a wall.

It takes a lot of skill to tell the audience pretty much everything we need to know about its story's world, tone, and characters in just ninety seconds, but that's MARRIAGETOXIN for you. The deadly efficiency doesn't just extend to our boy Hikaru's skills as a killer for hire. Sure, some of the exposition we get throughout this premiere is maybe a little clumsy, but the show has a lot of freaky assassins and worldbuilding details to deliver, so you can forgive a few overly direct exchanges about Hikaru's role in the Poison Clan and the political significance of his dating prospects (or lack thereof). Normally, such indulges could threaten to drag down an entire script, but it's hard to get bored when Hikaru is having a friendly drink with a freak who has bugs living inside of his mouth and clothes.

Studio Bones does a great job of making every scene of this premiere compelling in its own right with their keen sense of pacing and unsurprisingly excellent visuals. The bouncy production does a good job of capturing the gravitas of the show's more serious moments while still preserving the punk edge to its characters and visuals that keep things feeling so propulsive. It helps that our two protagonists share such undeniable chemistry as leads. Hikaru is the proverbial killer with a heart of gold—and it's impossible not to root for the guy who just wants to save his lesbian sister from life as his clan's fetus incubator. Meanwhile, Mei serves as a perfect foil and partner in Hikaru's quest to find a suitable bride. In addition to being mischievous and crackling with energy, how often do you have your action-star hero paired up with a bombshell, bisexual crossdresser as a partner in (marriage) crime?

I had high expectations for MARRIAGETOXIN, and I'm happy to report that this premiere lived up to every one of them. In a season that is already set to be stacked with great new shows and returning favorites, I reckon MARRIAGETOXIN will still stand tall above most of the competition as one of this spring's must-watch hits.

MARRIAGETOXIN is one of those rare shows I went into totally blind—well, beyond what the title implies anyway—and couldn't be more happily surprised with. Gero is a guy who has long-since accepted his “forever alone” status. And honestly, it's easy to see why. He's socially stunted and knows it. Rather than sending him to school, his family forced him to spend his whole life mastering how to kill people with poison. Even now, his family hasn't learned their lesson about the downsides of excessive control and are trying to force him or his sister, Akari, to get married and carry on the bloodline.

The relationship between Gero and his sister is at the emotional core of the episode. While Gero learned about poisons, it seems Akari led a more normal life and feels guilty about that—despite him never trying to put the responsibility on her shoulders. So when their grandmother gives her an ultimatium—that if Gero doesn't find a wife, she'll force Akari to get married instead, Akari elects to go home on her own terms. Of course, the big issue is that Akari is a lesbian and in a committed relationship. Going to be her family's brood mare means denying who she is on many levels. However, for the guilt and love she has for her brother, she's willing to do so.

Of course, Gero would never wish this path upon his sister. In fact, it's not that he's adverse to getting married: he just wants it to be a loving relationship and has no idea about how to go about finding a good partner given his job and social skills. So when he meets Mei, the marriage swindler, while on a job, she seems like the perfect dating coach—even once “she” turns out to be a “he.”

With this setup of a professional assassin looking for a lifepartner with the ultimate wingman in his corner, we get a series full of both crazy action and rom-com laughs. It's a fantastically fun time—and that's even before the visuals are brought into the equation. This anime uses fluorescent colors as highlights throughout which make the images on screen pop. Add to that some great camera work and excellent background design and you get a show that's just fun to watch.

While I have no idea if MARRIAGETOXIN can keep up this momentum beyond this first episode, I'll tell you one thing, I certainly intend on finding out.

There's a lot of fun, wild, over-the-top action series out there. There are goofy comedies that throw jokes at the audience multiple times per minute. Many of them try to mix in some character drama every so often, and some of them even do it well. Even then, I'm not sure I've ever seen a series quite as balanced as MARRIAGETOXIN while offering all of the above. At the very least, I'm certain few shows have made it look this effortless.

The key to its success lies in how sincerely it approaches its premise: Gero, an assassin of the Poison Clan, never plans on getting married. However, his sister calls in the middle of a job to tell him that she's being forced to marry a man to continue the family line despite being a lesbian with a girlfriend, he enlists his current target, a specialist in honeypot scams, to help him find a spouse in her stead. The problem is, he's so poorly socialized that he's going to need a lot of help, despite being handsome and wealthy.

The first part of the episode grounds us in Gero's situation, setting up his relationships with the people around him. Yes, he kills for a living and would be the first to admit that he's not a good guy, but he loves his sister and his friends deeply. It takes a deft hand to pull off a scene where a guy exits being carried away by bugs under his shoe as if he were riding a hoverboard, and Motonobu Hori and Kimiko Ueno are just the ones to pull it off. His sister's situation feels fresh and unique within the medium, much more interesting than the classic infantile imouto coughing weakly in bed at home (though there is some of that too). Mei Kinosaki, meanwhile, has the makings of a truly great foil to Gero: similar lack of scruples and motivation, but a completely different skill set. It all comes back to balance.

My one issue with the episode is, for all the setup feels perfectly paced, it only fills out the first two-thirds of the episode. This gives the final third a disjointed quality, tacked on to reach the final runtime. It's still fun! Just a bit wonky.

I suspect that neither of the Gero siblings was meant for the assassin life. I also have to wonder if their parents were aware of that, because Hikaru and Akari are awfully bright names for someone meant to be living in the shadows, but maybe that's me reading too much into something that's supposed to be amusingly ironic. In any event, these poor people are being pressured by their grandmother into producing offspring (not with each other!) to carry on the Gero family poisoning business, and that's a problem – because Akari has a girlfriend she loves and Hikaru is…let's go with “hopelessly awkward.”

This is one of those shows that I can tell is good but very much isn't for me. That's not to say that I didn't like aspects of it; Akari's storyline, brief as it is in this episode, is all about allowing her queer joy not be erased by a terrible elder, and I like the genderfluid aspect of Kinosaki's part in the series. Hikaru himself is also a good character; he's good at what he does, wants to do his part for his younger sister, and is astoundingly, unbelievably bad at normal human interaction. Watching him attempt to smile at several people in succession by trying new facial contortions is my favorite part of the episode.

But the rest of the plot leaves me a bit cold. Hikaru's not-so-hidden soft side even though he's a killer isn't quite enough of a hook, and while it's great that he wants a normal life and marriage, I can't help but feel that there's something mean underlying the story. He's essentially sacrificing himself for his family, because there's no indication that he actually enjoys being an assassin; he just happens to be good at what he was taught to do. He's getting Akari out, but at what cost to himself? Again, I'm probably reading too much into this, but it struck me as more sad than funny, and that's without considering my general distaste for stories about assassins.

This does look good, though. The chase scene with the car is exciting and dynamic, and I love that it brings Hikaru's earlier discussion with Kinosaki about creating highly corrosive cleaning agents as a hobby full circle. The art captures the look of the manga, too, which is always important, and I think fans of that will be pleased with this. It's not my sense of humor, but I believe I'm going to be the outlier on this one.