astronomer!cas having glow in the dark constellation underwear, and galaxy sweaters, and a lower back tattoo of his favorite astrological clusters
astronomer!cas taking dean to the observatory and showing him all of the different stars he’s focusing on, and tells him in detail about each one
astronomer!cas having a bath light that projects nebulas onto the walls and in the water, and sitting there for hours washing himself with the lights of the stars and cosmos