Sana Hudson (サナ in Japanese) is one of the 12 inhabitants of Balan Wonderworld. She is a woman who loves nature, and watches over birds and the forest.
Sana is an African-American woman with blue eyes, indigo-colored hair styled in dreadlocks, and gold hoop earrings. Her hair bears beads colored in orange, blue, yellow, and green. She wears a yellow, orange, and green headband that matches her tank top. She also wears light blue jeans and brown boots.
Sana loves taking pictures and looking at birds and nature in the forest more than anyone. After construction workers destroy the trees and environment and build a town, she becomes overwhelmed with panic, causing her to be corrupted into Cuckoo. After she is saved, she convinces the construction workers to build trees and birdhouses in the town for the birds to live. She is then able to look at them again.
- In the novel, her "name" while Wonderworld was under Lance's control was "Watcher of the Woods", or just simply "Watcher."
- In the novel, she seemed to be close friends with Eis Glover due to their similar aims to protect the things they care about.
- "Hiya!" "Yup, but you can just call me Watcher." - Sana's first words in the novel.
- "Wish I knew. Maybe it's cause I spend all day patrolling the trees. You know, to make sure nothing... bad, or anything, happens." - Sana, in response to Leo asking why her name is Watcher of the Woods.