This week, a year before the end of his One Life to Live contract, the Emmy-winning Roger Howarth departs Llanview, but not for the usual reason more money. Howarth, who's played Todd Manning since 1993, says it's ''really gross'' that his character, once an unrepentant rapist, is being redeemed as a newspaper publisher and heir. ''I just can't do those kinds of fairy tales anymore,'' says Howarth, twentysomething, who's moving from New York to L.A., where he'll try to break into movies. ''I'd rather be broke doing something I'm proud of.'' The actor gave notice last year, but only a few months ago did OLTL agree to let him go (on condition he doesn't do another soap for 12 months). ''I had a great time here for half the time,'' he says. ''But now it's in the best interests of the show to find a Todd who won't object to the material.''