From Pocket Comics:
It's the Fall of their senior year in middle school. Due to her parents' divorce, an emptiness has settled at the bottom of Azusa's heart. Her classmate, Itsuki, has experienced the same with his parents' divorce and sees through Azusa's feelings. Sharing this "something," the two of them promise to be together for the rest of their lives despite all the changes happening around them. What is a bond that lasts forever? What is a real bond like? This is a story of how the two of them move forward while in doubt and fumbling around for answers.

Original Webtoon