"Saki Yumihara is a prominent character in the Japanese manga ""Original Sin."" Saki serves as the main love interest of the protagonist, Tatsuki Sakura. The manga revolves around the idea of the ""original sin,"" and Saki's character plays an essential part in its storyline.

Saki is depicted as a beautiful young woman with long black hair and stunning green eyes. She is a popular and well-liked student at her high school and has many admirers due to her charming personality and beauty. Saki is also admired for her intelligence and is a math prodigy, which is why she attends a prestigious high school.

Saki's character adds a sense of mystery to the manga as her true intentions and feelings are ambiguous throughout. At the beginning of the story, Saki appears to be the perfect girl-next-door, but as the story progresses, it is revealed that she has a hidden past and secrets that she is trying to keep hidden from her peers.

Tatsuki Sakura, the main protagonist, is completely smitten with Saki and is determined to win her over, even though he knows that she has secrets. Saki, for her part, also has feelings for Tatsuki but is hesitant to get too close to him due to her fears of being exposed.

Throughout the manga, Saki's character is developed as she struggles with her secrets, her feelings for Tatsuki, and her role in the ""original sin."" Her character's development makes her one of the most intriguing in the series, as readers are left guessing about her true intentions until the very end.

In conclusion, Saki Yumihara is a crucial character in the ""Original Sin"" manga. With her beauty, intelligence, and mysterious aura, she serves as the perfect love interest to the protagonist, Tatsuki Sakura. Her complex character development adds a layer of intrigue to the storyline, making her one of the most captivating characters in the series."