The Weird World of TSF: Gender Switching Fiction in JAV

Don't Think About It Too Hard. Just Enjoy It.

If you ever come across the acronym “TSF” in Japanese media (whether mainstream or porn), you’ve just wandered into one of the more interesting themes to come from Japan. TSF stands for Transformation Sexual Fiction which involves the idea of someone transforming into the other sex. While the term is fairly modern, there is a rich history of these types of fiction: from traditional Japanese folklore to computerized visual novels involving futanari furries. There is a wide breadth and depth to the various forms of TSF, whether they are mystical(e.g. The cursed springs of Ranma ½) or metaphorical(e.g. A folk tale with cross-dressing twins), or as an interesting narrative concept (e.g. the first part of the Anime Movie, Your Name). TSF just pops up everywhere in Japanese media(and in other cultures too), and oftentimes it’s a curious exploration of the human power dynamics and social nature of sexuality.

STAR-775:

My Name Is Iori Kogawa Suddenly One Day, Ms. Iori And I Switched Bodies

Starring: Iori Kogawa

Release Date: May 3, 2017

Runtime: 2 hours 2 mins

Studio: Fitch

Director: Mackerel

In a fairly basic treatment of TSF, starring the lovely Iori Kogawa. Nothing too original here, just a guy body switching with Iori Kogawa and exploring all sorts of humorous situations that come with it. We have Your Name to thank for this one. Makoto Shinkai’s movie was very popular when it was released in 2016, and the reverberations of it were thoroughly felt all over the internet. This particular movie, you can easily tell the influence in the production, building upon the mood of the movie it’s parodying.

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A Male College Student Who Likes To Play RPG Games As A Girl Gets Transformed Into A Female He Won't Acknowledge That He's Been Cumming Like A Bitch, But This Adorable Little Cunt Is Trembling Just From The Excitement Of Walking Outside In A School Uniform Shinichi Yamagishi Hajime

Starring: Ichika Matsumoto

Release Date: December 7, 2020

Runtime: 2 hours 28 mins

Studio: KaguyahimePt/Mousouzoku

As a big fan of Ichika, I had to include an Ichika Matsumoto TSF here. This one's more of an Isekai where an introverted gamer boy wakes up as cutie Ichika Matsumoto. With her attempts at boyish mannerisms and masculine language, it’s charming to watch Ichika in this role. She is a natural comedian and her charisma lends itself well to goofy movies like this.

STAR-976

Yume Takeda Gender-Bent Gangbang

Starring: Yume Takeda

Release Date: May 3, 2017

Runtime: 2 hours 6 mins

Studio: Fitch

Director: Mackerel

Another version of TSF, sans the magical elements. In this JAV, Yume Takeda dresses up as a man on a mission. Cutting her hair like a man, wearing mens’ school uniform, and strap binding her chest. In order to infiltrate the all-boy’s school and find the bullies that were bullying her stepbrother. However she gets caught in the act, and eventually gets used for the bullies sexual pleasure. Visually, the boyish looks of Yume Takeda getting hard fucked by a train of dicks is erotically confusing.

RCTD-388

Life Switch ~ Ultimate StepFather And StepDaughter Couple ~ Rika Tsubaki

Starring: Rika Tsubaki

Release Date: March 11, 2021

Runtime: 2 hours 10 mins

Studio: ROCKET

Director: Route Yamazaki

This one’s a doozy. Rika Tsubaki and her stepfather were photographed by a mysterious photographer and then ended up switching bodies on her wedding day. Now the stepfather, who is now in Rika’s body, must consummate the marriage to a confused husband. Somewhere along the line Rika(inside her stepfather’s body) bangs her own body(containing her stepfather’s soul). That’s wild.. Hilarious acting from Rika adopting her stepfather's mannerisms (and vice versa) in this funny TSF. Just don’t think about it too hard.

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TSF Punishment Feminization Prison

Starring: Emi Sakuma, Sumire Seto, Ako Momona

Release Date: September 22, 2019

Runtime: 2 hours 10 mins

Studio: ROCKET

Director: Kiyoshi Miwa

In this fictional dystopian world, Japan decided that capital punishment is not harsh enough for its hardened criminals. Now convicted criminals are made to undergo an experimental new punishment even worse than the death penalty: to be literally transformed into a woman. Those who are penalized with this procedure get sent to a harsh prison where, if they misbehave, they get punished sexually by cruel and virile guards. Who knew we’d get such a poignant criticism of the Japanese penal system in JAV?

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The Ultimate Daydream Item Evolution Series The Dark Side Of Transformation Into Female Skin 3 - A Descent Into Evil Through The Cursed Skin - A Super Evil Woman, Cums With Mask

Starring: Rika Aimi, Kurumi Suzuhana

Release Date: January 8, 2021

Runtime: 1 hours 10 mins

Studio: ROCKET

Director: Kiyoshi Miwa

A male patient stuck in the hospital develops a crush on cute nurse Kurumi. Then he finds a strange fleshy mask that allows him to skin change into a hot woman(Rika Aimi). After going through the motions of masturbating with his new female body and banging a male patient, he then proceeds to manipulate and seduce nurse Kurumi for his own pleasure. A TSF with a dark lesbian twist. Rika Aimi is so hot.

RCTD-106:

I Just Became A Woman... But My Female Transformation Was Incomplete, So Now The Lower Half Of My Body Is Hermaphrodite!? 2 The Male Prohibition Communal House Edition

Starring: Rika Mari, Ria Kashii, NIMO, Ichigo Suzuya

Release Date: May 24, 2018

Runtime: 2 hours, 12 mins

Studio: ROCKET

Director: Route Yamazaki

Our protagonist is in despair as he is rejected by NIMO who likes girls. He takes a magic potion that turns him into a woman (Rika Mari)…. But somehow he still has his dick… and a brand new pussy. Now living as a hot futanari(aka chick with dick), hilarity ensues as he tries again with NIMO who is pleasantly surprised at all the sexual posibilities of banging someone with both genitals. Somewhere along the line, NIMO also brings him to her stepmom, Ria Kashii. Now they just have threesomes galore! TSF just lends itself to nutty narratives like this..

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ROCKET 17th Anniversary User Request Festival - Super Swap stepFamily - Two Days Of stepDad, stepMom, And stepDaughter

Starring: Kurumi Sakura, Mayu Suzuki, Machi Ikuno

Release Date: August 7, 2025

Runtime: 2 hours 2 mins

Studio: ROCKET

Director: Taro Kanbe

In a fairly recent release, the TSF narratives are evolving too. This one is a three parter. Stepmom, Stepdad, and Stepdaughter discover a magic book that switches them up. Stepdad goes into Stepdaughter’s body. The stepdaughter wakes up in her stepmom’s body. Stepmom wakes up in the stepdad’s body. (You can follow along with the arrows in the cover photo if it's confusing). And then plot twist, stepdaughter gets to have a new detachable magic penis. A stepfamily comedy for the ages. Again, if you don’t think about it too hard, it’s hilarious.

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Kuso Miso Technique

Starring: Uta Kohaku Reiko Sawamura

Release Date: August 12, 2012

Runtime: 1 hour 57 mins

Studio: MOODYZ

This one needs a bit of explaining. If you look at the cover photo, you’ll see a bunch of drawings of manly dudes there. You see, this is an original JAV collaboration with the source material being…. A Gay Manga? For some reason, MOODYZ chose a popular explicit yaoi manga called the Kuso Muso Technique?… And then they cast Uta Kohaku and Reiko Sawamura in place of the muscular male leads???… and then attached dicks to them so it won’t be a gay film but a futanari film??? And then they copied the gay sex scenes in the comics (with actual anal scenes) with this new futanari version???? Lots of question marks here??? Not sure if this counts as TSF??? But in a meta sense, it kind of is??

SPRD-962

If Dad Became a Woman… Kazama Yumi!?

Starring: Yumi Kazama

Release Date: July 27, 2017

Runtime: 1 hours 39 mins

Studio: ALLEDIN

Director: Rokusaburo Mishima

If you thought that previous one was weird, that won’t prepare you for the last one, the ultra weirdest of the bunch even if its the least complicated in the list. A middle aged man struggles in reconnecting with his stepson. Upon discovering his stepson’s interest in mature JAV, he gets a sex change to turn into a sexy MILF (Yumi Kazama) in order to win his stepson’s affection. Then, like with most TSF, it evolves sexually from there. Just WTF. Talk about stepdaddy issues but this is just beyond scuffed. But, you know… if you don’t think about it too hard, it’s pretty hilarious.

As usual, That’s all from me, Vez. See you in my next article!

What do you think of TSF in JAV? Do you have a favorite example? Hit me up in the comments!