Konoha Hoshinomori presents herself as a refined and responsible young woman in her role as the Student Council President of Hekiyō High School. In public, she upholds a composed and dignified image, though in private, her personality is far more relaxed and multifaceted. She expresses admiration for both attractive girls and boys, as seen when she blushed at Eiichi Misumi’s appearance and again when Keita Amano passionately spoke about video games suggesting that she may be bisexual.

Much like her older sister Chiaki, Konoha is a devoted gamer with extensive knowledge of classic titles. She is also an avid fan of erotic games (eroge), though she prefers to keep this interest a secret. On one occasion, she even disguised herself to reclaim a game from her sister without revealing her identity. When others discover her interest in eroge, she becomes aggressively insistent that they keep her secret, demonstrated by her demanding that Keita remain silent about it.

Konoha cares deeply for Chiaki and actively supports her romantic interest in Keita. She even went so far as to impersonate Chiaki’s online gaming aliases in order to help orchestrate their relationship. Despite growing increasingly frustrated with Chiaki’s timidness and Keita’s obliviousness once even striking Keita out of exasperation Konoha continues to prioritize her sister’s happiness above her own. Her dedication remains unwavering, even as she herself falls in love with Keita.

Eventually, Konoha confesses her feelings to Keita before Valentine’s Day, with Chiaki present. However, the act is strongly implied to be a strategic move intended to push Chiaki to be more assertive rather than a genuine pursuit of her own romantic interest. In an unlikely alliance, she even teams up with Keita’s younger brother, Kōsei Amano despite their mutual dislike in order to support Chiaki and Keita’s relationship.

It is later revealed that Konoha harbors a sense of envy toward Karen Tendō. Wanting to avoid being overshadowed by her, Konoha chose to attend a different school, hoping to build her own identity and reputation. This internal conflict resurfaces when she hears others comparing her to Karen. Despite the temptation to sabotage Karen’s relationship with Keita either for Chiaki’s benefit or her own Konoha ultimately chooses integrity. When given the perfect opportunity to drive a wedge between the couple, she instead reassures Karen of Keita’s genuine feelings. This act of maturity earns her a degree of newfound respect from Kōsei.

Konoha Hoshinomori has long dark blue hair styled in twin ponytails and purple eyes, features she shares with her older sister, Chiaki Hoshinomori. While Chiaki later cuts her hair shorter, Konoha retains her longer hairstyle, giving them distinct appearances despite their similar features.

Although her exact height is not officially stated, Konoha appears to be approximately the same height as her sister.

Konoha Hoshinomori is first introduced while fulfilling her duties as Student Council President at Hekiyō High School. After concluding a council meeting, she privately expresses amusement at being surrounded by attractive girls, before realizing she has other plans. Disguising herself in casual clothing, she heads to a local game store, where she browses the selection of erotic games, a personal interest she keeps hidden from others.

While in the store, she spots Keita Amano and Eiichi Misumi, recognizing them by their Otobuki High School uniforms. She is impressed by Eiichi’s appearance and considers Keita’s looks average. After being noticed while performing a random physical gesture, her strange behavior unsettles both boys. However, upon overhearing Keita speak passionately to Eiichi about an obscure but meaningful game, Konoha becomes captivated by his perspective. His words stir her own feelings of inadequacy and her longstanding sense of being “second best” compared to Karen Tendō. Moved by his sincerity, she purchases a similar game.

Back home, Konoha relaxes on the couch when her sister, Chiaki, joins her. Upon noticing the game Konoha bought, Chiaki becomes suspicious, and Konoha clumsily tries to explain before attempting to reclaim the game from her. Later, Konoha finds Chiaki in a daze, troubled by her growing interest in an anonymous boy she interacts with online. After making an offhand comment and receiving a hit from her sister, Konoha borrows the family computer while Chiaki goes out.

While using the computer, Konoha accidentally falls asleep in Chiaki’s bed. She wakes up just as Keita is on the verge of discovering that Chiaki is both “Mono” (his online gaming friend) and “Nobe” (his favorite game developer). In a panic, Chiaki falsely claims that both online personas are actually her sister’s, much to Konoha’s shock. Still, understanding Chiaki’s shy and reserved nature, Konoha agrees to go along with the deception and pretends to be both “Mono” and “Nobe” when introduced to Keita.

From that point on, Konoha plays an active role in supporting her sister’s romantic feelings. She interacts with Keita under the guise of Chiaki’s online aliases, even as her own feelings for him begin to deepen. On one occasion, Keita catches her buying eroge, and Konoha sternly forces him to keep it a secret. Later, when Keita innocently praises her supposed “work” as a developer, she becomes flustered and furious, punching him in a fit of embarrassment and frustration over his continued obliviousness.

The given name Konoha (心春) is composed of the kanji ko (心), meaning “heart,” “mind,” or “soul,” and ha (春), meaning “spring.” Her surname, Hoshinomori (星ノ守), combines hoshi (星), meaning “star,” and mori (守), meaning “guardian” or “protector.”