The Blue Monster is a background character seen exclusively in the video "This Is My Girlfriend".
They are asked by the Purple Monster to take a picture of him and his "Girlfriend", to which they turn around and slowly float away.
Needless to say, they are a resident of The House, and were likely collected by the Purple Monster.
Physical Description[]
They have a rounded blue body with a large blue blob resembling a nose in front of their eyes.
The eyes themselves are surrounded by very dark rings.