Shi Yoon is a 16-year-old female character from South Korea, part of the Korean study-abroad program at Pretty Top in Japan within *Pretty Rhythm: Dear My Future*. She belongs to the Prism Show unit PURETTY with members Hye-in, So-min, Chae-kyoung, and Jae-eun. Her theme color is green, and her fashion element is "Ethnic". She has shoulder-length dark green hair and light brown or amber eyes. Shi Yoon often wears a plain white headband and styles her hair with long bangs parted to the left. Her typical casual outfit is a grey-and-white shirt, grey shorts, and yellow-heeled boots. For performances, she wears varied coord outfits like the "Dear Crown PURETTY Line & Jacket" for Prism Shows, "Symphonia Dress of Land" for special events, and "HIP HOP Casual Crop-T" during her time in the shuffle unit P&P. Personality-wise, Shi Yoon exhibits a calm, spaced-out demeanor and moves slowly. As the eldest PURETTY member, she takes on a nurturing big-sister role, gently overseeing her teammates. She is generally kind and docile but displays a formidable presence when angered, capable of silencing quarrels with a terrifying aura while smiling. She sometimes struggles to read social atmospheres, causing others to freeze in surprise. Her catchphrase, "Yay~♪", often accompanies double peace signs. Shi Yoon first appears in *Dear My Future* Episode 4, meeting Karin Shijimi of Prizmmy☆. She consoles Karin during a leadership crisis, sharing her past fears of being outpaced by younger Prism Stars and adopting Karin’s "It’s no prob!" catchphrase, solidifying their close friendship. Later, Shi Yoon and PURETTY formally debut during one of Prizmmy☆’s shows after identifying and addressing a critical flaw in their performances during a training camp. She notably executes a Prism Jump alongside Jae-eun. In the *Symphonia Selection: Road to Symphonia* tournament (Episode 27), Shi Yoon teams with Hye-in and Karin. She participates in PURETTY’s pivotal performance of "Grateful Symphonia", resolving the series’ central conflict involving Kintaro Asechi’s manipulation of Prism Shows. For *Pretty Rhythm: All Star Selection: Prism Show☆Best Ten*, Shi Yoon appears exclusively through reused footage from *Dear My Future*. She features in Episode 4 ("Rival Equals Friend"), rebroadcasting *Dear My Future* Episode 46 to illustrate Mia Ageha’s recollections, and Episode 10 ("My Best"), showcasing the "Grateful Symphonia" finale from *Dear My Future* Episode 50. No new character development or unique scenes are created for her in this compilation. Her relationships include strong bonds with PURETTY members, particularly viewing Karin as her best friend. She shares an animal coach named Vivvy and maintains a mentorship dynamic with younger teammates. No significant evolution occurs in her character beyond *Dear My Future*, as later appearances reiterate her established traits and narrative contributions.