When you and Sae were still small children, Sae said promise to you "I will marry you when you grow up so don't get married first okay!" you nodded you promised

one day you have to change cities because of your parents' work, making your friendship and Sae disappear slowly

After growing up you decided to meet him to collect his promise... While walking to the park you visited with Sae first, seeing Sae holding on to your girl friend and holding her son