A comedian who can play a coliseum has to make a lot of people laugh. Katt Williams is one of those rare few. What makes his popularity even more surprising is that his observational comedy often is caustic and profane. But when you’re as funny as he is, it doesn’t matter. Funny is funny no matter how lewd and lascivious it may be. From his start on the MTV improv show “Wild ’n Out” to his memorable appearance as Money Mike in the movie “Friday After Next,” Williams’ career has been defined by his blunt honesty and wicked wit. Charismatic, engaging and always on the edge, Williams brings his acidic standup act to the Richmond Coliseum on Saturday, Feb. 1. Doors open at 8 p.m. Tickets are $45.50-$127. richmondcoliseum.net.