[Bakemonogatari] Cute but violent!? A thorough explanation of Araragi Koyomi's younger sister, Tsukihi

2025.07.29

Araragi Tsukihi is the younger sister of Araragi Koyomi, the protagonist of the "Monogatari" series. Despite her gentle and adorable appearance, she has a rather violent personality. There are many mysterious aspects to her, but what is her true identity? Tsukihi's profile image
Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

Contents

Tsukihi Araragi

Tsukihi Araragi is a character who appears in the "Monogatari" series of novels and anime, created by Nisio Isin. She is the younger sister of the protagonist, Araragi Koyomi, and wears traditional Japanese clothing on a daily basis. She is petite and very adorable.

The Other Side

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

However, despite her intelligent and gentle appearance, she has a violent personality. She can be quite extreme, such as casually pulling out a kitchen knife. She is very close with her older sister, Karen, but is extremely obsessed with her brother, Koyomi. According to her brother, she is cunning, hysterical, and emotionally sensitive.

She is close with her older sister, Karen

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

She is very close with her older sister, Karen, and they are always together. The two, with a strong sense of justice, volunteer for social reform activities and are known as the "Fire Sisters of Tsuganoki Junior High School."

Fire Sisters

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

While her older sister Karen is very active and in charge of actual combat, the intelligent Tsukihi serves as a strategist. When her brother, Koyomi, says of their activities, "Your sense of justice is fake," Tsukihi retorts, "It's not a pretense, it's justice itself." However, Tsukihi says she doesn't possess the same passionate sense of justice as Karen. While Karen and Tsukihi are passionate and diligent, Tsukihi seems to be very calm.

She actually has a boyfriend!?

It's rumored that Tsukihi has a boyfriend who is older than her. His name is apparently Rousokuzawa-kun, but he never appears in the story and is rarely mentioned, making his existence a mystery.

Real! Or Lie?

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

By the way, her boyfriend is said to resemble her older brother, Koyomi. Tsukihi claims that they have a pure and loving relationship, but it's interesting to wonder if this is a lie to get her brother's attention, or if he really exists.

A Girl Who Loves Her Big Brother

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

Tsukihi, of course, loves her brother, and there are often heartwarming scenes of them venting their frustrations and arguing. Koyomi describes Tsukihi as cunning, and this seems to be due to the way she leads her brother on with cute and clever words, such as "You can be mad at Karen, but don't be mad at me."

Forbidden love!?

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

The two are close enough to go beyond the roles of brother and sister, but Tsukihi seems to be feeling lonely because her brother has recently become a little more mature and obedient. She was extremely upset when Koyomi said, "I'll introduce you to my girlfriend" at the end of the story, so it seems like it will be a while before she becomes independent from her brother.

Tukihi's True Identity

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

In episodes 8 through 10 of "Nisemonogatari," Tsukihi's true identity is revealed. The shocking truth is that Tsukihi is a "monster." First, Koyomi realizes that Tsukihi's body is not normal because all of her past injuries have completely disappeared.

The Appearance of Kagenui Yozuru

Then, a person named Kagenui Yozuru, an expert on the supernatural, suddenly appears. At first, it is thought that he is targeting Koyomi, but in fact his target is Tsukihi. The two have come to bury the supernatural Tsukihi. While there, Tsukihi's body is blown away by Ononoki Yotsugi, a supernatural being brought by Yozuru, but she remains unharmed. She is a supernatural being called the "Shidenotori," who is immortal until the end of her life.

What is the Shidenotori?

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

Now that it's clear that fire is a supernatural phenomenon, what exactly is the "death bird"? The death bird is also known as the little cuckoo. While the Lesser Cuckoo is a real bird, it possesses a trait known as brood parasitism, laying its eggs in other birds' nests and having the nest's owner raise the young in their place.

In fact...

Their physical characteristics, such as abnormally fast hair growth and the ability for scars to disappear completely, are the result of a supernatural phenomenon. The death birds in the story also possess these traits, but the Lesser Cuckoo in the story uses a human body instead of a nest. Therefore, the Lesser Cuckoo is born as a human, lives as a human, and dies as a human. Aside from the fact that it is a fake and is immortal until death, it is no different from a normal human, and it seems unaware of this.

Platinum's Cute Voice Actor

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

The voice of Tsukihi, whose catchphrase is "Platinum pisses me off!", is provided by Yuka Iguchi, a voice actress and singer. Iguchi made her voice acting debut in 2002 as Sapphire, the Gamers mascot character for "G.G.F." The following year, in 2003, she made her anime debut in "Di Gi Charat Nyo," and formed a voice acting unit for both works, which she continued to work with until it disbanded.

Top 10 Araragi Tsukihi Quotes

"W-why is Nadeko in my bed? I was supposed to be hugging you!"

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

This statement is already crazy (lol). Tsukihi is a serious bro-con. She naturally sleeps next to her brother. It's wonderful to have a little sister who sleeps next to you.

"Just being by your side is enough. Just loving you is enough. That kind of thing sounds nice, like it's all ladylike and modest and all good, but don't you think it's really meaningless?"

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

Deep. It's so deep. Is it possible that Tsukihi is rejecting the idea of being a Yamato Nadeshiko girl? I don't understand that. Is it like she's saying she should focus more on her own love life?

"You've gotta wake up already, right!?"

Source: Bakemonogatari ©Nisio Isin/Kodansha, Aniplex, Shaft

I said this while lying down. If I were sleeping like this in a kimono, I'm sure I'd be able to see what was visible depending on the angle. Surely anyone would want a little sister with whom they could have such a lazy conversation in the morning!?

"Don't make fun of kimonos."

A word from Tsukihi, who loves kimonos. Tsukihi loves kimonos so much that she even wears them as everyday clothing around the house. However, it seems like Tsukihi often wears them casually.

"What? Didn't you hear me? Are you not listening to what people are saying? Or are you saying you can't or don't want to answer my question?"

It's about time for the hysterical little sister, Araragi Tsukihi, to show off her true colors! I can already sense a bit of insanity just from her words. It feels like three seconds before the moon and fire bomb explodes.

"That's shocking... I mean, it's thunderous! My brother, who once publicly declared something pathetic like, 'Making friends weakens me,' has found someone he likes."

Tsukihi can't hide her surprise that her brother has a girlfriend. That's a really clever way of putting it. This phrase is a perfect example of Nisio's unique style.

"It's just us, and your brother's mom and dad, so they're bound to have their own personalities."

He spoke these words with a slightly languid expression. "It's just us, and your brother's mom and dad." The Fire Sisters and Araragi Koyomi have one thing in common: their sense of justice and kindness.

"I hate it, I'm not plotting anything or anything—that's what Onii-chan always does. He always treats me and Karen like kids. He's just a worrier."

SHAFT's signature pose, this one line from Shaft. If she said this with her hair tied up in a towel and big eyes, you'd probably say "Oh, I see!" But don't be fooled. She's definitely up to something!

"Don't just grow up on your own. It's boring."

Those words were directed at her older brother, who had grown into a grown-up. As her older brother grew closer to adulthood, Karen graduated from junior high school. Karen must have felt left behind. Tsukihi is so cute when she's feeling lonely.

"I'm not the type to regret things that much, but that's why I sometimes find myself wondering why I didn't regret something back then."

Another profound statement. Regretting something allows you to reflect on it, learn from it, and grow. Tsukihi regrets missing that opportunity. I'm sure she'll grow from it.

Summary

Have you been able to appreciate the charm of Araragi Koyomi Tsukihi? There's a stark contrast between his appearance and his personality, and some people may find that appealing. While there are many cute girls in the "Monogatari Series," be sure to keep an eye on Araragi Koyomi Tsukihi.