A brofessional is a dude who has devoted himelf fully to bro activities. Obviously this includes beer drinking, watching sports, playing videogames, listening to bro music, hitting on slutty girls.
However, what truly distinguishes the brofessional is that he, upon graduation, finds a job that encourages or accomodates this lifestyle.
For example: Investment Banker, Lacrosse Coach, Client Relations Management, Beer Company Representative, Admissions Officer, College Counselor, Vineyard Vines Employee, Physical Therapist.
"Bro, our lacrosse coach is a brofessional. Did you seem him inhale those beers during flip cup last night at ATO?"
"Yeah, dude. He was crushing everyone at Beer Pong too. I think he hooked up with that freshman whore, Maria. I can't believe he's 27."