|“||Are you stupid?||”|
—Saki Kawasaki, My Teen Romantic Comedy, SNAFU!
Hachiman Hikigaya states that Saki is tall and slender. Her eyes are light purple in the anime, and she has a beauty spot under her right eye. It's said that her legs are smooth and it's stated that she has long flowing hair that hangs between the middle of her thighs and her knees. Her hair was described as "blueish" by Hachiman.
Saki is usually seen in the school uniform, though she wears it in the most disheveled and relaxed state (not to school standards). She has two buttons of her shirt undone and doesn't tuck it in. Sometimes she doesn't wear the blazer and if she does it is unbuttoned. Sometimes she ties a grey cardigan around her waist. She wears handmade scrunchies in her hair and around her wrists.
When first introduced, Saki is very calm and serious, like when Hachiman saw her underwear (Episode 5, Volume 2). She is initially introduced alone and holding a lighter, indicating she may smoke sometimes. She is only seen playing with the lighter in the anime. This is never addressed or alluded to in either the Light Novel or Anime, it would be safe to assume she does not smoke.
Saki appears cold and distant to others. She can be curt, stubborn and frank. She avoids small talk and doesn't like to talk with others, especially about her personal issues. Saki seems like a delinquent who is always late for class, dresses poorly, and is impolite to others. Saki can appear aggressive to some, both in defence of herself and when being "polite". Saki's aggressiveness stems from the fact that she can't express herself properly, and just plain social clumsiness.
Later in the series, she is shown to be a kind and loving older sister, and fierce protector of her family. Saki regularly texts someone during class (presumably her younger brother), often with a smile on her face. She often run errands involving Keika or Taishi. It is revealed she is not a delinquent but actually very hardworking. She had great grades and in order to improve them through summer school she worked part-time jobs to afford extra classes.
Even after she stopped working on night shifts and other part-time jobs, Saki still appears tired, lazy and reluctant to chit chat, indicating that nothing in ordinary high school teen life interests her.
Saki is known to be adept at housework and simple chores. She picked up many skills looking after her younger siblings. She often made dinner for her siblings in her middle school days, which shows her skill in cooking. Saki is also skilled in sewing both by hand and by sewing machine. She shows her skills when making costumes for the class play during the Cultural Festival, and when making outfits for the Athletic Festival. Hina Ebina noticed her hand made scrunchies, and alterations to her school uniform.
In Volume 2 her skills are listed as karate and making soft toys.
She is shown to be somewhat athletic as she participated in the athletic festival during the girls event. She was also part of the broadcasting team with Ebina and Yumiko Miura.
Addressed / Nick names
- "Are you stupid?"
- "What does it matter where I go? I haven't bothered anyone."
- "I just need money." 
- "I'm not working for money to spend playing around. Don't lump with those idiots."
- "I told you, you didn't need to know. I plan to go to college, and I don't want to burden you and our parents with that."
- The name Saki means "sand" (沙) (sa) and "hope" (希) (ki).
- Saki's surname Kawasaki means "river, stream" (川) (kawa) and "cape, peninsula" (崎) (saki).
- Saki is allergic to cats.
- Saki has worn black laced underwear to school.  
- Saki sometimes uses slang.
- Saki brings a cheap $1 lighter to school sometimes.
- Saki dotes on her younger siblings, just like Hachiman Hikigaya dotes on his sister.
- Saki is shown to be bad with scary things.
- Despite the fact that Saki is good in house chores, she only can make plain food like Rice Krispie Treat.
- ↑ 1.0 1.1 My Teen Romantic Comedy SNAFU Anime: episode 5; prologue
- ↑ 2.0 2.1 My Teen Romantic Comedy SNAFU Anime: episode 5; part A
- ↑ 3.0 3.1 3.2 My Teen Romantic Comedy SNAFU Anime: episode 5; part B
- ↑ 4.0 4.1 My Youth Romantic Comedy is Wrong as I Expected; Light Novel: Volume 2; prologue
- ↑ My Teen Romantic Comedy SNAFU Anime: episode 5; part A-B