No. The man isn't lying. He was ugly based on the story and he's helping the girl but he can't show his appearance. He's afraid that the girl will get scared then go away, then he'll never see her again for he was deeply in loved with the girl.

So here's the whole story. *THIS IS NOT MINE*
https://www.reddit.com/r/bangtan/comments/8m50ul/what_do_you_think_is_the_meaningstory_behind/

Once upon a time, in an Italian village called La Citta di Smeraldo, there was a man with a grotesque appearance who hid himself in a small secluded castle. He was lonely and his only joy was growing flowers in the garden. He grew to fall in love with a girl who came to his garden to pick flowers. Secretly, he learned that she was poor and sold flowers for a living. However, he could not reveal himself to the girl because he was scared she would hate his hideous appearance. Instead, he decided to make a flower that the girl could sell at an expensive price. After many attempts, he made a flower that never existed before and filled his garden with it. *However, the girl never came for the flower...she died before his act of sincerity could reach her.*