
Seiri-chan is a heartwarmingly absurd manga for the modern period.
Like a lot of manga, Ken Koyama’s Seiri-chan is named after its protagonist. However, even longtime fans of anime/manga may be struggling to remember another franchise with a character named Seiri in it.
That’s because Seiri isn’t a traditional Japanese name. Instead, it’s the word for “period” or “menstrual cycle.”
Yes, Seiri-chan is the latest, and arguably most unexpected, entry in Japan’s ever-lengthening list of anthropomorphized characters, following colleagues drawing inspiration from mushrooms and Japanese swords. Rather than trying to render the liquid state of monthly lady flow, Koyama draws Seiri-chan as a pink, vaguely heart-shaped entity with full red lips and a white cross for a nose.
While Seiri-chan can be seen punching a woman in the midsection on the back cover of the first collected volume, she’s generally presented as a more benign figure in the manga. Each chapter has Seiri-chan spending time with different women during her once-a-month visit, often as they’re experiencing some sort of personal crisis or emotional dilemma. For example, in the scene below, Seiri-chan makes her long-awaited appearance in front of a woman named Kaori, who recently slept with a married coworker with no contraceptives being used. “Men who don’t use a condom are the worst,” Seiri-chan declares, while giving Kaori a reassuring hug.
▼ “I don’t know what I would have done if you hadn’t shown up today,” says Kaori, relieved that the night of passion hasn’t resulted in an unwanted pregnancy.
In a later chapter, Seiri-chan gives a pep talk to convenience store clerk Riho, who’s always had an inferiority complex about her less-than-glamorous looks and thus is unwilling to believe the handsome man who confessed his love to her is serious about wanting a relationship.
Seiri-chan also takes time to console Momoko, a cafe waitress and aspiring novelist who’s been sent into a spiral of depression after discovering that her coworker Ippei, who she had a secret crush on, has started dating the beautiful half-Japanese Chloe, yet another of her coworkers.
Sometimes, though, instead of being quietly supportive, Seiri-chan is psychotically violent, like when she punches this man in the face while shouting “Menstrual Punch!” before injecting him with a drug that causes him to have periods as well.
Through written and illustrated by a man, Seiri-chan has quickly built up a sizable female fanbase, including our own female Japanese-language reporter Anji. “Koyama’s a guy, so how does he understand women’s feelings so well?” said Anji after reading through the volume. “Whether I’m laughing or crying, I can always identify with the women Seiri-chan visits.”
With its outlandish premise and episodic nature, Seiri-chan seems like it’d be a perfect fit in the world of late-night short anime programming, and we wouldn’t be surprised to see an adaptation in the near future. Who knows, maybe the franchise will become a big enough hit that we’ll see a brand-new batch of anime-themed menstrual pads go on sale in Japan.
Photos ©SoraNews24
[ Read in Japanese ]






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