- "My name is Billy and I saw you the other day at the merry-go-'round. I think you are very pretty and I like your blue dress and the songs you sing about angels."
- ―Billy Parson
Billy Parson is the son of Harold and Gloria Parson. He was a little boy at the time of Rapture's collapse. Billy was fascinated by a Little Sister that he saw near the merry-go-round in Dionysus Park one day, and he decided to leave her a gift. He made an audio diary confessing his love for the girl (whom he described as the "yellow-eyed girl") and directed her where to find the gift. The gift was a box containing a single rose. It can be found near a crushed Big Daddy in a code locked room in the basement storage area of the park. The fate of Billy is unknown, however his rose was later found by Subject Delta and his leaving of the code allowed him to upgrade his weapons.