
“She comes once a month,” promises the new trailer’s ominous opening line.
Here at SoraNews24, we’ve been scrunching our stomachs, angrily downing pints of chocolate ice cream and rolling around disconsolately on our bedspreads waiting for news on our favorite web manga mascot Seiri-chan. A star of the web manga circuit, Seiri differs from a lot of cutesy mascots meant to draw in tourists or showcase wares. How so?
Well, Seiri is getting her own movie.
All right, all right. There’s another key thing that sets Seiri-chan apart from the fluffy, dewy-eyed mascot crop – she represents the menstrual cycle. Her antics in her native web manga, written and illustrated by Ken Koyama, include draining women of blood with a big syringe and punching men in the stomach. Her name also means menstruation! The secondary characters in her manga are understandably dismayed whenever she arrives (unless in the midst of a pregnancy scare.)
Seiri’s jump from comic panel to big screen was announced in February and its staff kept tight-lipped about its details, refusing to confirm anything besides a live-action adaptation. A curious choice, considering Seiri’s sloppy heart shape, staring eyes and white cross nose, but Japanese directors would know how to translate that into a live-action movie better than most.
The movie will focus on International Rising Star recipient Fumi Nikaido, who plays a work-driven fashion editor constantly dreading each time Seiri raises her unnerving fluffy head. The cleaning lady for the fashion office, played by Sairi Ito, laments her father’s enthusiastic sex life with his new girlfriend and resorts to trolling people online to keep her demons at bay.
As the manga has been praised for its sensitive depiction of the difficulties that can come with menstruation, the movie is being billed as a sensitive way to understand reproductive health – while offering a serious helping of laughs along the way. As Nikaido herself mutters in the trailer, “the period’s bad enough, but what really sucks is how nobody understands how bad it is.”
▼ “I wish men had to go through this pain even it was only once a year,” the protagonist grumbles, and Seiri is happy to oblige
Despite the harrowing contexts in which Seiri appears in the movie, she ultimately seems to serve as a kind of life coach for the two protagonists. Both women are struggling with meaty life problems only exacerbated by their periods, and Seiri’s gentle counsel helps to get both of them back on the right track. But there’s a new mascot in town, as well..
▼ Meet Libido-kun.
The trailer seems to be doing well on YouTube, where comments range from users’ own trials and tribulations with Aunt Flo to excitement for the movie and its star-studded cast list.
“I’m a guy, but I wanna check this out. I haven’t experienced it, and no one taught me about it at school, so I have no idea how hard it is to deal with. I’m glad they’re making a movie so we can learn about it in a fun, easy way.”
“I wish we could watch this in health class.”
“Fumi Nikaido looks amazing in this role.”
“My period hit right as I was watching this trailer.”
The movie releases its punchy period pandemonium on September 8, so until then tide yourself over with a comfy blanket, some gentle exercise and maybe this cheery comic about the whole sordid ordeal.
Source, images: YouTube/oricon
Related: Seiri-chan Official Website
● Want to hear about SoraNews24’s latest articles as soon as they’re published? Follow us on Facebook and Twitter!




Massive menstrual flow character will be Japan’s newest movie star
Osaka store catering to menstrual goods has staff wear badges saying if they’re on their period
Anthropomorphized menstrual cycle is Japan’s newest comic book star
We score an exclusive interview with viral Twitter star Otodo-chan, Kochi Aquarium’s scary mascot
10 times to avoid traveling in Japan in 2026
Our 52-year-old pole dancing reporter shares his tips for achieving your New Year’s exercise goal
Umamusume anime girl plushie recalled for having parts she absolutely should not have【Pics】
Kumano Kodo pilgrimage route Newport sandals released by Keen
Draw like a Studio Ghibli anime artist with exclusive watercolour set approved by Hayao Miyazaki
Parody of One-Punch Man opening is the punchiest thing you’ll see today【Video】
Japanese actress wows in stunning edible dress made of vegetable slices【Video】
Japan Sets Guinness Record for Synchronized Mascot Dancing 【Video】
Adorable New “Pokemomo” Brand Goods Coming to Pokemon Center Stores Across Japan
We visit a Japanese cafe famous for John Lennon and epic pancakes
Japanese beef bowl chain Sukiya’s 2026 Smile Box lucky bag basically pays for itself
Hayao Miyazaki says Happy New Year to Studio Ghibli fans with new art for Year of the Horse
Ramen restaurant’s English menu prices are nearly double its Japanese ones, denies discriminating
Starbucks Japan ready to get Year of the Horse started with adorable drinkware and plushies【Pics】
Top Japanese cosplayer Enako returns to Comiket after 6 years, creates mayhem with admirers
Cup Noodle tries an authentic Jiro-style ramen, but something’s not quite right
The best Starbucks Japan Frappuccinos we want to drink again in 2026
We revisited Sweets Paradise after a decade to see if Japan’s dessert buffet still delivers
That time Seiji called JASRAC to ask why he didn’t get paid royalties for his song being on TV
7-Eleven Japan starts new temporary luggage storage service in over 300 branches
Disillusionment at Tsukiji’s tourist-target prices led us to a great ramen restaurant in Tokyo
Starbucks teams up with 166-year-old Kyoto doll maker for Year of the Horse decorations【Photos】
Tokyo considering law requiring more trash cans following litter increase in heavily touristed area
Tokyo’s Tsukiji sushi neighborhood asks tour groups to stay away for the rest of the month
Tokyo event lets you travel back in time, for free, to celebrate 100 years since Showa era start
Japan may add Japanese language proficiency, lifestyle classes to permanent foreign resident requirements
Lacquerware supplier to emperor of Japan and Pokémon team up for new tableware
Starbucks Japan releases new zodiac chilled cup drink for 2026
Survey asks foreign tourists what bothered them in Japan, more than half gave same answer
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
We deeply regret going into this tunnel on our walk in the mountains of Japan
Studio Ghibli releases Kodama forest spirits from Princess Mononoke to light up your home
Major Japanese hotel chain says reservations via overseas booking sites may not be valid
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】
No more using real katana for tourism activities, Japan’s National Police Agency says
Starbucks Japan reveals new sakura drinkware collection, inspired by evening cherry blossoms
Updated cherry blossom forecast shows extra-long sakura season for Japan this year
Human washing machine pods coming to Japanese hotels【Photos】
Leave a Reply