I've recently noticed this more often in anime, even good ones like Code Geass or Hyouka, but it's still annoying as hell. You have a goofy, comedic side character who's basically there to contrast bad jokes with the protagonist's dry wit, or complete ineptitude with the ladies to contrast the main character attracting them like flies.
God damn, I need more books that center on the goofy sidekicks!
Some mildly suitable examples I can think of include the Blacktongue Thief (which fits almost perfectly), or the Lies of Locke Lamora (fits less well, but still not bad).
by T_Lawliet