Spy x Family is a comedy shonen anime with stylish 1960s-inspired Cold War antics and intrigue, but it also has time for heartwarming, character-driven storylines. As Westalis' best spy, the handsome Loid Forger/Agent Twilight is torn between his solemn duty as a WISE spy and his growing affection for his found family, proving that even the coldest spy can still have a warm heart.

Now there's another secretly loving spy in Berlint: the silver-haired WISE spy Fiona Frost, or Agent Nightfall. She's also an expert at hiding her true feelings and speaking in code, but Anya's telepathy soon reveals the truth -- that Fiona is a true anime kuudere bursting with love for Loid, all hidden under an ice queen exterior.

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How Fiona Frost Lives Up to the Kuudere Archetype

Fiona Frost daydreaming about wedding

A kuudere is a character who's distant and aloof on the outside while hiding their true feelings until the last moment. Kuuderes are patient and composed people who will wait to show their genuine affection for the right love interest and coldly brush off everyone else. Unlike a tsundere, who will get angry and defensive about their hidden amorous feelings, kuuderes like Fiona Frost merely mask their hearts with an unreadable cold exterior or poker face. Moreover, unlike timid dandere characters, kuuderes are confident in themselves, hiding their affection not because of fear or self-doubt but because they are naturally unexpressive. Generally, kuuderes are introverts and somewhat asocial, leading a quiet, stable life where everything must happen for a good reason.

Kuudere anime characters aren't scene-stealers like tsunderes are, since kuuderes have comparatively passive and quiet personalities. Nonetheless, they still stand out with their calm, matter-of-fact attitude about love, creating an amusing gap between their warm hearts and their cool exteriors. Kuuderes might also have subtle but easily recognizable visual cues, often having black, white or silver hair that's probably neat and stylish rather than messy and stereotypically "anime." Kuuderes also rarely raise their voices and have calm facial expressions, especially in the eyes.

Fiona lives up to all this and more as a model kuudere. She has neat, silvery hair in an attractive but simple style, along with a classy yet forgettable outfit. Most of all, Fiona maintains her composure as an emotionally detached and disciplined spy, refusing to give away any of her thoughts or emotions to anyone, not even Loid or Sylvia Sherwood. Fiona is calm, patient and methodical as an introverted kuudere, all while her heart is ablaze with excitement and passion for Loid.

Inwardly, kuuderes are more lively and creative, and sure enough, Fiona is practically squealing with joy just to be in the same room as her love interest. She is eager to replace the dandere Yor Forger as Loid's wife for Operation Strix, happily picturing her newlywed self supporting Loid as a fellow WISE spy and wife. Amusingly, kuuderes don't typically pick fights with love rivals or criticize others, but the competitive kuudere Fiona does just that, inwardly scorning Yor as an unworthy wife for Loid. This proves that while kuuderes follow the same basic formula, they are all unique people, and Fiona simply happens to be a kuudere with a hidden aggressive mindset.

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How Fiona Frost Compares to Other Anime Kuuderes

reina aharen is offering lunch

For the most part, Spy x Family's Fiona is an archetypical kuudere anime character, checking off most of the boxes while adding a few twists. This means Fiona can be fairly compared to other kuudere characters in recent anime titles, and the similarities are many. One example is the petite Reina Aharen from Aharen-San is Indecipherable -- a rom-com high school anime about the whisper-quiet Reina who just wants to be heard and make friends. Like Fiona, Reina has neat silvery hair, a composed and mature attitude and a wild imagination. Reina is calm and quiet on the outside as a kuudere, but around her love interest Raido, a fellow kuudere, Reina shows her heart. Reina amused viewers with her goofy antics, from freestyle rap to submarine periscopes to arcade games, all with a straight face as a true kuudere. Aharen is bursting with love, but she will only show it in modest, controlled bursts.

A few male kuuderes also compare well to Fiona Frost, including Fruits Basket's Yuki Sohma. He is more disciplined and easygoing than his tsundere cousin Kyo, but he also has insecurities and imposter syndrome to deal with. However, despite his many burdens, Yuki presents himself as a polite and calm young man, immensely endearing him to the girls at his school. He views Tohru Honda as his best friend and privately told her how much she inspired him, and he quietly but earnestly reached out to the troubled Machi Kuragi and fell in love with her.

Hirotaka Nifuji, the co-star of Wotakoi, is another male kuudere who could probably relate to Fiona on many levels. Like her, he has a classy but also unremarkable appearance as a well-dressed office worker, and he rarely shows any emotion with that blank face of his. Inwardly, Hirotaka is fiercely passionate about video games, and he also loves his ultra-extroverted girlfriend, Narumi Momose. Hirotaka is slow to express that affection even in private, but he might give Narumi previews of it with his goofy texting style and his eagerness to play video games with her and their mutual friends. Like Fiona, Hirotaka is cold on the outside but bursting with energy and creativity on the inside when he's around the right people.