“Sae is intelligent, professional and serious, although her actual maturity is debatable. A workaholic, Sae is very strict in both her work as prosecutor and guardian for her younger sister, Makoto, constantly telling her to focus on her studies and such. With many responsibilities, Sae is always working due to Japan's work pressure, and is very stressed and exhausted. She must care for Makoto, almost putting her in a single mother's role. Her father dying in the line of duty and forcing her to raise Makoto acts as her very sore spot. She resents Makoto, as the Niijima sisters’ father throwing his life away in the name of justice forced her to raise her sister alone. Because of her father's death, Sae views the concept of justice as meaningless. This has made her hyper-competitive and obsessed with getting ahead, to the point of telling Makoto that success is all that matters in life. This is to her detriment, as it results in many unjust prosecutions that she blatantly rigs in order to maintain the court's reputation, even if the people indicted by her are innocent.” - Persona 5 Wiki

Voice Example

https://www.youtube.com/watch?v=IstQEy_G0Yg