"Lois Lane, Millionaire" Superman Daily Newspaper Strip - December 4, 1944 to February 10, 1945
Lois Lane stands to inherit a small fortune from her recently deceased great-granduncle, unless an unscrupulous lawyer can take advantage of the strange stipulation - Lois, as the sole heir, if unmarried, has ten days to find a husband.
Superman is, naturally, her first choice, But the Man of Steel’s dogged persistence that Lois should fall for him in his Clark Kent guise leads to the closest near-reveal of his dual identity to date (excluding only his deliberate and misunderstood unmasking in a previous issue of Action).
Superman’s connubial slipperiness leads Lois into the arms of a dashing con man who, ultimately, underlines the problem with anyone pitching woo at Superman’s Girlfriend - who in their right mind wants to get Superman angry at them?
Of course, Lois fails to inherit the money, but it all works out for the best, and the romantic status quo is reestablished in time for the next adventure.