Ultra Woman, buy the Smallville book! It's actually very good and it helps support a pairing we much rather prefer. Here's the source link for Clark quitting (along with 8 pages of spoilers.) USA Today article "Clark Kent makes a major life change in new \'Superman\'"
CLARK: No. I'm just worried I'm a jinx.
JONATHAN: A jinx?
CLARK: Yeah. Let's face it, ever since she's known me, Lois's been kidnapped, frozen, pushed off buildings, almost stabbed, poisoned, buried alive and who knows what else, and it's all because of me.
-"Contact" (You're not her jinx, you're her blessing.)
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