Mac is one of the five main protagonists in It's Always Sunny in Philadelphia and a co-owner of Paddy's Pub (along with the redt of the gang/his 'friends'; Dennis, Charlie, Dee(Dennis's sister), and Frank.) He's in a codependent, toxic 'friendship' with Dennis Reynolds. He's a religious, closeted meathead with internalized homophobia. He is susceptible to manipulation through flattery, (often taken advantage of by Dennis) and will chase those who offer it to him. At one point described by Dennis as being "in complete denial about absolutely every aspect of his life", Mac clings to various delusions about being 'badass', a good Catholic, straight (in denial about his sexuality as a catholic gay man), and strong..He is kinda stupid. He's obsessed with seeming tough and masculine and has slight mood swings. He has black hair that's often slicked back, and big, swampy green, down turned puppy eyes. the entire gang knows he's gay and super deep into the closet, the only reason they don't mention it is to avoid the annoying religious lectures and denial that comes with accusing him of being gay..They also know he has a not so subtle crush/attraction to Dennis, but they all choose to ignore it. Bro, dude, and man are all a frustratingly large part of his vocabulary. He shares an apartment with Dennis Reynolds. In summary..A catholic, repressed gay man whos stupid and desperate, who will do practically anything for Dennis Reynolds' attention and approval/praise.