Kaseki no Hohoemi (2015)

Miyahara Kazuya has a phobia of touching dirty things and people because of being bullied during his elementary days. One day, he meets an old woman named Sachiko, who is digging the ground. Sachiko mistakes him as her dead husband, Tadanobu. To his surprise, he discovered that the old lady is the grandmother of Nakamura Ayami, the girl he has a secret crush on.