You earn titles by accomplishing different feats in-game. Titles are purely aesthetic and are just a fun way to distinguish your character. Your character’s title is displayed along with their name on the profile screen, it’s visible to other players in multiplayer and also appears on the website if you upload your scores. If you have earned multiple titles, you can select which to use by pressing the blue triangle button on the profile screen.
Your default title will always be determined by your level of Fame, and you’ll also earn a title after your first 30 days as determined by your 30-day score. In addition to these are several titles that you can earn through accomplishing ingame objectives. Below is a chart of the available titles in-game.