Born in the Eagle Nebula as a spiritual entity, she traveled to earth to observe the human race. She then took form as a canine dog and befriended Rigby, her partner in crime. She and Rigby travel the world seeing it's wonders and helping people. Silhouette reverted Rigby's old ways of stealing and chaos to a life of kindness and reward. They now live in Colorado in a nice-sized cabin in the woods. Silhouette takes human form to sell her flowers and artwork during the day and reverts to her canine form during the evening to be with Rigby. She is kind-hearted, ghost-like, sensitive, calm, organized and devoted.

Tail:
Ever changing. Changes spectrum depending on mood and/or time of day. Her tail is her bridge to her heritage. It is a piece of space that has been somehow preserved in the oxygen atmosphere. It has a strong force field around it, as it is the heart of Silhouette's body. If it dies, she dies. Since Silhouette is a Stardog, when she dies, the tail will explode and cause a super nova, just like all stars do. Fortunately, Silhouette is able to return to the Eagle Nebula whenever she pleases, without means of earthly transportation. So when she does die, she can safely do so many light years away.

Eyes:
Whenever she feels, Silhouette is able to reflect any galaxy within her eyes.