Originally Reveille was given free reign of the campus. However, since 1960, she has been cared for by a Mascot Corporal, a sophomore cadet in Company E-2. The Mascot Corporal is chosen within his unit each spring, and Reveille lives with him for that year: she goes to class with him, out on dates, and goes home with him for the holidays. He, in turn, escorts her to all of her functions and Aggie engagements.
Miss Rev, as she is affectionately known on campus, is the highest-ranking member in the Corps of Cadets and wears five silver diamonds (the Corps Commander only has four). That means if Miss Rev falls asleep in a cadet’s bed, the cadet must find somewhere else to sleep since she outranks him. Tradition also dictates that if Reveille is in class and barks, the professor should end class because Miss Rev is bored.
https://www.tamu.edu/traditions/aggie-culture/reveille/