Yu Ishigami is a main character in the anime series 'Kaguya-sama wa Kokurasetai'. He serves as the treasurer of the Shuchiin Academy Student Council. Known for his gloomy demeanor and blunt honesty, Yu often finds himself in awkward situations with his peers. Despite his introverted nature, he is highly intelligent and skilled in accounting and technology. Throughout the series, Yu's character undergoes significant development as he learns to open up and form meaningful friendships with other council members, adding depth to the series' comedic and romantic elements.