ToniKawa Theory: Tsukasa is 1000+ Years Old

I've been watching and reading #TONIKAWA (Tonikaku Cawaii) lately. It's a Manga about a Married Couple's life as newlyweds. I love how wholesome the story is. Like the its name says, ToniKawa Manga/anime is Just. So. Cute!


Spoilers for the Anime's First Season

Yuzaki Nasa, a genius middle school student got hit by a truck. He was saved by "the cutest girl in the universe." He fought the pain to ask her to go out with him. She says she'll only do that if he marries her, her promises her to marry only for her to disappear. Two years later she comes back and introduces herself as his wife.

The fandom describes the story as diabetic. I find it very accurate. There's No Drama, No Love-Triangles, No over-arching conflict. Just two people who chose to marry and one-up each other in love~ The story is about learning how to compromise and become a better person.

The Mystery of Tsukasa

Having said that, there's a mystery element to ToniKawa. Nasa married Tsukasa without knowing anything about her. As the audience, we get introduced to her gradually over the series course, and many things we know right now imply that Tsukasa is immortal, or at least a human being who lived for very long.

No matter what Tsukasa is, she's not normal. The first hint that something is up with the girl is in the first chapter. When she comes back she looks the same as she was three-years prior. She says that she's 16 years old, and I find it hard to believe that she looked the same when she was 14-years old. (Though it's anime logic, anything can happen...)

Another hint is how she talks about the grandmother. She calls her by name, which is considered rude in Japan. But if she was the older one, it won't be a rude thing to say.


She was always said to have met her younger adopted sister (many) years ago, still, she looked the same. She even used "I was normal 16 years old girl" when she was speaking about the past. I don't believe that this is a translation error!

Theory: Tsukasa is Over 1000 Years Old

Tsukasa also talks about Historical figures in a way that implies she knew them personally. She says things like "The prince (of this historical place) won't mind." She claims that she dislikes history, yet she's very knowledgeable about the history of Japan. She once referred to taking pictures with her husband in Historical places as "overwriting memories."


In a Manga-only scene: she drew a katana while mentioning that it's been long since she carried this type of sword. Nasa's father was afraid of drawing this same katana because it required a special handling way.

All of that in small dialogue pieces, and in a causal way that her husband won't think too much of her words. (Though he probably won't care because she's just so cute.)


The series offers a bunch of these subtle hints so frequently, that this theory is all-but-confirmed. This is a theory that the story encourages and expects the audience to have. ToniKawa's story plays on the expectation that you have this theory in mind while reading, and I love the author for that!

The Moon, and Kaguya Hime

ToniKawa series has a lot of moon Motifs. (The official full English name contains: "Fly Me to the Moon.") Tsukasa herself is often compared to Kaguya-Hime, a girl who went back to the moon at the end of her story. Tsukasa even has a piece of the moon in her room in her original house! Tsukasa's adopted sister said that "Grandmother borrowed the moon-stone to ease her."

The first chapter even states: This is the continuation of Kaguya's story and I think this is significant for some reason!

Cuteness First! Who Cares about Mystery?

You have to put in mind, that ToniKawa as a series is not about this mystery. The author keeps giving us hints every now-and-then to keep our curiosity running, but the series has been heartwarming long enough that I expect Nasa & Tsukasa's love to stay strong and beautiful even if she turned out to be immortal, even if her husband realized the truth, and even if there was no cure for her.

The theory however makes me ask more questions. If she was 1000+ years old, why she decided to marry now? Why she doesn't tell Nasa about it? (Probably because it's embarrassing.) Why the characters who know her past won't say anything? These are the questions that make me want to read more, and I hope to see where the story goes from here~

Please put your Thoughts in Comments~

  • First image is taken from the anime. All other images are taken from the Manga.
  • This article is crossposted here on Hive and on
  • Special thanks to @holovision for inviting me to join to the Fan Theories community.
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