The quest is unlocked after completing the All Hyrule, United scenario.
"The minister of Hyrule found a strange note written by his son, with a list of items sought by the young man. Eager to please his child, the minister askes for help retrieving the items."
"When you presented the minister's son with the items from the list, he was surprised yet relieved. As it turned out, his aim had been to cull monsters and thereby lessen his father's burden."