Aka to Ao (赤と青)

Kaguya-sama: Love Is War - Stairway to Adulthood

Years after graduating from high school, Kaguya Shinomiya finds her old photo album and reminisces about when she was a part of Shuuchiin Academy's student council. At the time, Kaguya had just started dating the president Miyuki Shirogane, and the two were hopelessly in love. With each wholesome and silly memory from their past, Kaguya is filled with bliss.