Mion Sonozaki

Mion Sonozaki is one of the main characters in the Higurashi no Naku Koro ni anime and games.

Mion is Shion's twin sister, and the heir of the Sonozaki house. Mion is the more well-known sister of the Sonozaki twins, as well as the more mature, stable, and tomboyish one.

Appearance
Mion has long, pale green hair and teal eyes. Her bangs part in the middle and she ties her hair into a ponytail. She has a trim figure and a large bust. She has a demon tattoo which is never shown. The Sound Novels and opening to the First Season suggest a full back tattoo which could not be applied to a child in one day. In subsequent episodes where her back is partially exposed, the tattoo is not seen.

During her school days, Mion wears a white short-sleeved shirt with a green (anime) or red (games) tie and wears a yellow, unbuttoned vest. She also wears a long reddish-pink skirt, black socks, and brown shoes. During her free days, she wears a yellow shirt with a slight black turtle neck, a white sweatshirt tied around her waist, blue jeans and brown shoes. She also wears an airsoft gun in a holster on her shoulder, though it is never used in the anime.

In the anime 's first episode, she wears different casual clothes: a white shirt with a dark-red collar, shorts, a green sweatshirt tied around her waist and a purple gun holster.

At the end of Taraimawashi-hen, 10 years after the Great Hinamizawa Disaster, Mion appears as a 27 years old adult. Her hair became significantly longer, constantly hiding her face. She's also described as unnaturally pale and "almost as white as her pajamas or the hospital's curtains". As a result of her severe mental trauma and amnesia, her eyes also became rather lifeless, constantly giving Mion an empty, blank stare. Due to 10 years of hospitalization and lack of exercise, her basic motor skills deteriorated to the point of being described as awkward, almost mechanic. Her speech also became slow, silent and unenergetic.

Personality
Mion acts boyish, energetic, and confident, often teasing her friends. She is a very cheerful and sociable girl who enjoys games. As the leader of the after-school games club, she organizes various card or board games, which she has become extremely good at, partially through cheating. She is the club member that tends to win the most, but as Rena reveals to Keiichi, she was the biggest loser at the beginning of the club. Mion designs most of the "punishment games" that the loser must perform, but, again, in the beginning, she often had to do them herself. It is a tribute to her determination that she has advanced so far in skill.

Although Mion seems very self-confident and tomboyish, it is revealed that she is quite girly. This is an important point in Watanagashi-hen and Meakashi-hen, where Keiichi decides to give a doll he won to Rena rather than Mion, thinking that she would not like girly things; in Meakashi-hen,, this event is shown to trigger the development of the Hinamizawa syndrome in Shion, leading to the deaths and murders of many people including Mion herself, at the hands of her own sister. However in Minagoroshi-hen, Keiichi is able to resolve this fate by giving the doll to Mion instead (of course Mion is a little hesitant to take it, as she says, "Wh-what?! I don't like that sort of thing! I'm sharp and spunky as you always say!" Keiichi, however, tells her that she's still a girl to him and she ends up revealing her girly side by saying, "Yes, I will treasure this doll," and looking lovingly at the doll.) Mion is seen to be somewhat shy around Keiichi in moments where her crush on him is obviously in plain sight, and because of her shyness, she is unable to open up to him. In Higurashi no Naku Koro ni Kira, she is shown to still have the doll, keeping Keiichi's promise on taking good care of it.

As the heir to the Sonozaki family estate, she must act very formal and responsible when dealing with family matters. As a result, Mion has another side of her personality that contrasts with her normal self. When she assumes this role, she becomes almost completely expressionless and very serious. She is seen to be very straightforward and always goes directly to the topic, avoiding any other conversation that might interrupt. A good example of this side of her is from Meakashi-hen, where she forces Shion to rip off three of her own fingernails as punishment, despite the fact that she cares deeply for Shion and later rips off three of her own as retribution.

Trivia

 * Only a very small number of subbers have noted the fact that Mion says "oji-san" very clearly in many lines where she refers to herself. Oji-san can mean either uncle or old man. MangaGamer's translation of the games includes this detail as "Uncle Mion".
 * During the ending special of the 2nd episode of Kai, when Hanyū recites the "ABC's of Higurashi" and asks Rika to provide an input for the letter S, Rika replies, "Shii and Mii go 'Gugegegege'!" This guttural sound is heard during the Zombie Tag game when Shion and Mion were acting as bloodthirsty zombies, and also in the 5th episode of Rei when Mion receives a violent uppercut from a love-cursed Rena.
 * Her and Shion's father is a yakuza boss. Befitting her role as a yakuza heiress, Mion's school uniform is of a style stereotypically associated with the "sukeban" delinquent subculture.
 * She is 165 cm and weighs 52 kg.