From this Design Trend article (emphasis on poorly written sentence mine):
A new father-daughter chastity phenomenon is leeching across the United States.
“Purity balls” are similar to weddings, except the father marries his twelve-year-old daughter. The goal is to maintain the girl’s virginity until marriage.
During the ceremony, the fathers present their daughters with purity rings, and the duo become boyfriend and girlfriend, the Daily Mail reported.
“You keep this on your finger and as of this point you are married to the Lord and your father is your boyfriend,” the father says as he hands his daughter the ring.
The girls then “silently commit to live pure lives before God through the symbol of laying down a white rose at the cross, before engaging in a wedding-type dance with their father.”
Having sex with, kissing or touching a man (other than their fathers) before marriage is strictly prohibited.