River is one of the main characters in To The Moon. She is the wife of Johnathon Wyles. She has Asperger's Syndrome, a form of autism. She first met Johnny at a fair when they were young children, where they agreed they would meet on the moon if they ever lost each other. This is the reason that Johnny's dying wish is to go to the moon.
River dies before the main events of the game begin. She was diagnosed with a late-stage terminal illness and refused treatment because the cost would prevent Johnny from finishing the house they were building that overlooked the lighthouse, Anya. As a child she thought stars were lighthouses, spread out across the sky. They lived a lonely existance, far from the other stars so she wanted to "befriend" one in her lifetime so that it wouldn't be lonely.
She has a very strong attachment throughout her life to a stuffed platypus that was given to her by Johnny at the fair.
After Johnny confesses he first started dating her because he wanted "someone different," she realizes he lost his memory of their first encounter at the fair and begins to make various origami rabbits in an attempt to remind him of the night they met. After asking Johnny if he ever created shapes from the stars, they used the moon and stars in the sky to create a constellation resembling a rabbit. She even creates one with blue paper for the head and feet and yellow for the torso, as it resembles the yellow moon that makes up the belly of the rabbit constellation (also, her wedding dress was blue and yellow.). This was her best attempt to return Johnny's memories, because Asperger's Syndrome makes direct conversational interaction rather difficult.