Describe Mr. Harvey as Susie first sees him. Why does she fall for his line?

Susie introduces her killer as a man in the neighborhood. She knew of him because her mother liked his border flowers, and her father once had a conversation with him about fertilizer. The day that Susie is killed, she is walking home from school through the cornfield in the snow. It is after dark. George Harvey startles her. He tells her he built something and asks if she wants to come see it. She tries to excuse herself to go home, but he insists and calls her by her name even though she hasn’t told him her name. At the time she thought maybe he knew it because her father frequently talks about how Susie tried to pee on Lindsey when Lindsey was a baby because Susie was so jealous.