Blue Journey is a subunit formed as part of the Blue Journey musical project for Hololive Production. The project will see a series of consecutive single releases over the span of 3 months. The songs are set to explore the listener's feelings and invoke a moment of introspection. The first original single for the project featured Minato Aqua, Houshou Marine, and Tsunomaki Watame. The second single features Sakura Miko, Houshou Marine, and Omaru Polka.