Is Sara a flat or dynamic character?

Sarah Ruth is a flat character as she remains religious, unattractive and uninterested in frivolities throughout the story. When Parker first meets her, he observes that he wouldn’t want anything to do with her, because of her “dry hot and rough hands” and her plain looks. Also, she is not attracted to his tattoos, something that quite surprises Parker as he had never before met a woman who did not like his tattoos. She refers to the tattoos as “vanity of vanities." It is her rejection of his tattoos that torments Parker.
Later on, after he marries her, Parker observes that she has not changed much. She is plain-looking and, to make matters worse, pregnant—something that makes her even less attractive to him. He thinks that she obsesses over righteousness. This is why she does not imbibe, smoke, use foul language, or even use body makeup.
However, Parker forgets that Sarah comes from a religious family and lives her life the only way she knows how to. Her father was a preacher who must have taught her the scriptures well. Parker may have thought that marriage would finally change Sarah Ruth into a doting, more agreeable wife. However, she remains unchanged and this makes him “gloomier than ever." The text states that each morning, Parker would leave determined not to return, yet came back in spite of everything.