Natsuki

Natsuki is seemingly a brash, direct, and arrogant girl, but internally kind and sweet, a result of her insecurity. She is based on the anime archetype of a tsundere.

However, despite being impulsive and speaking without thinking, Natsuki genuinely cares for her friends, and even when she has anger issues, she doesn't enjoy fighting or arguing with people. Over the course of the game, we see that she cares for Yuri and even delivers a "poem" to the protagonist, asking him to help Yuri, as she fears that if she talks to her, it will cause more arguments.

She also has a love for manga, particularly slice-of-life manga and baking cupcakes. She keeps her manga collection to the Literature Club out of embarrassment, and while the rest of the club obviously knows about her interest, they are still hesitant to talk about it. Natsuki also likes cute things, such as cupcakes with cat faces. She also likes poems with cute and happy words, though her own poems are about sad things, such as being persecuted for her hobbies. Her simplistic writing style always puts her at odds with Yuri.

Natsuki doesn't like being called "cute," even when she acts cute or does cute things, and she will deny any claims from others regarding this. However, she feels much more comfortable expressing her sweet side once she knows people won't tease her about it. Natsuki hates being taken seriously, whether it's for her writing, her hobbies, or just her general behavior.

Natsuki likely learned to be ashamed of herself and her hobbies from her judging classmates and implicitly abusive father, making her aggressive nature a defense mechanism. This is also implied in her secret poem, "Things I Like About Papa."

Natsuki has pink hair, just like her eyes. She also has a bow-shaped hair clip on the right side of her front hair and two red ribbons that form two small twin tails. The rest of her hair is short, with a small fringe framing one side of her face and a few strands of hair on her forehead.

Natsuki wears the traditional school uniform, just like the other characters, for most of the game. On her route, on day 3, she wears a light pink ruffled skirt with black trim and a short-sleeved white shirt decorated with a small light pink cat head. Two black bra straps are visible beneath her shirt.

The protagonist suggests that his short stature is caused by being younger than the rest of the cast, but Monika implicitly thinks it is due to malnutrition.

The Literature Club is a club originally started by Monika. It makes whoever is the Club President realize that the game's "exploit" is within them and that they have control over it. This may be due to the cliché in visual novels of having an instructional or guiding character who provides advice on how to play, a role the president can fill because they don't have a romantic route.

Monika - Founder/President of the Club (Act 1-3)
Sayori - Vice-President (Act 1) and President of the club (Act 4)
Yuri - Club Member (Act 1) and Vice-President (Act 2)
Natsuki - Club Member
Protagonist - Club Member

The Literature Club has very few members compared to other clubs at the school. In Act 2 and Act 4, the club doesn't actually have enough members to form an official club, conveniently needing the Protagonist to become one.
While there is very little information about other clubs, Monika mentions that she left the Debate Club due to drama among the members. The Anime Club is also mentioned at the beginning of the game.
In Act 1, the protagonist mentions that there is an "Anime Club" which he wants to join, ignoring the Literature Club.
The club's vice-president always suffers the same fate: Sayori in Act 1 and Yuri in Act 2 die.

In Act 1, it is implied that Natsuki's father has a problem with Natsuki reading manga, so she keeps it in the club room instead of taking it home.

In Act 2, it's implied that Natsuki's father is abusive and malnourished. During the scene where Natsuki and the protagonist read manga together, Natsuki says, "My dad would beat me up if he found out about this." Natsuki later faints from malnutrition, and Monika gives her a protein bar, which revives her. Monika then tells the protagonist that this happens frequently because Natsuki's father doesn't feed her enough.
In the special poem "Things I Like About Dad," it's revealed that Natsuki's father is often too tired to do anything, usually arriving home late. It also says that Natsuki's father tells her how to dress, makes negative comments about her friends and hobbies, and doesn't leave her things alone.