“The Tokyo U Promise from 15 Years Ago: Diary”
“Tōdai no yakusoku wa jūgonen mae Nikki na” (東大の約束は15年前 日記な)

Keitaro sneaks a peak at Naru’s diary and finds out about a promise that apparently she made many years ago to go to Tokyo U. Then Keitaro begins to think that he made his promise to her. She is very insecure about talking about it and repeatedly denies it. As it turns out, the promise was supposed to be to a man named Seta.