The performance 'Cassiopeia's Secret' is a first approach to an artistic, emotional, and scientific examination of the relations between music, sexology, gender identity, and astrophysics. It utilizes medical sensors and the technique of sonification to make sexual arousal audible. Moreover, there are tactile stimulators controlled by music and data generated by cosmic phenomena. The sensors and vibrators are hidden beneath a futuristic attire called a Pleasure Space Suit designed for sexual relaxation during long space travels. The story is about an experiment performed by Cassiopeia, a genderfluid Space Girl wearing the Pleasure Suit, and her friend and scientist, Dr. Aurélie. It is a simulated mission to an exomoon where the audience perceives the sonification of Cassiopeia's sexual arousal, the sound of celestial signals, and Aurélie's stimulating music as a futuristic symphony of pleasure.