He fell in love with her when he was a child, but he couldn't express it and cut off a lock of her hair as a souvenir.
When he grew up, he "reacquainted" with her with the help of his friends. But his pressing steps made her very helpless.
She had a car accident and became a vegetable, but he never left her.
After a long time, when she woke up, she lost her memory.
He really got to know her again, and the reenactment of the scene restored her memory. She also cut off a lock of his hair as a souvenir.
A loving memorial.