WARNING: The following contains major spoilers for Batman: The World, available now from DC Comics.
The tense romance between Batman and Catwoman is one of the most iconic love stories in comic book history. While Bruce Wayne and Selina Kyle's attraction towards one another has always been strong, the mutual difficulty each of them has with opening up to others on an emotional level has always been the main factor keeping the two of them apart, perhaps even more so than their conflicting stances on the law.
Despite this, Batman and Catwoman have always proven their love for each other in the moments when the two of them have been allowed to let down their guard around each other. One of the stories featured in Batman: The World, an anthology that follows the Dark Knight through a series of international adventures, demonstrates just how far Catwoman has to go to get Batman to honestly admit whether or not his feelings for her are real, and thanks to a little bit of divine intervention her efforts are rewarded when he answers that question with an honest and heartfelt reply.
"Paris" by Mathieu Gabella and Theirry Martin opens with Catwoman breaking into France's Louvre Museum, presumably to steal the priceless artwork up on display inside. Almost immediately she's confronted by Batman, who's followed her across the Atlantic. As she playfully leads him on a chase through the moonlit halls of the museum, an unusually emotional Batman desperately tries to convince Catwoman to leave, warning her she'll be in danger if the Louvre's new curator finds out she's robbing it. Catwoman doesn't listen; instead, she takes the time to enjoy the fact that Batman's being so protective of her and teases him with the knowledge that she's already stolen at least one painting. Upon hearing this, a furious Wonder Woman steps out of the shadows and reveals that she's the new curator Batman was talking about.
To Batman's surprise, Catwoman isn't at all surprised by Wonder Woman's entrance. Instead, Selina reveals that she knew that Diana was the curator the whole time and uses a smoke bomb and some quick acrobatics to swipe Wonder Woman's Lasso of Truth before either hero can react. By the time the smoke vanishes, Catwoman has successfully lassoed Batman with the golden rope, which renders anyone it ensnares incapable of telling lies. Catwoman leans in close and whispers something in Batman's ears, and he quietly says, "Yes, until the day I die."
As Bruce and Selina embrace each other, a dumbstruck Wonder Woman realizes that Catwoman's break-in was a ruse to get Batman to admit that he loves her. As the morning comes, Diana tells Bruce that, for once in his life, he should follow his heart. Taking her advice, Bruce and Selina walk off into the sunrise hand-in-hand.
Batman and Catwoman's love life has been a roller coaster of romantic highs and lows, with both of them coming through for and disappointing one another more times than either of them can count. The two have gone from enemies to uneasy allies to lovers over the course of their relationship, and the two almost got married during Tom King's run on Batman. While Selina's decision to break off their engagement damaged their relationship for some time, the two ultimately reconciled when they teamed up against Bane and the Flashpoint universe's version of Batman's father Thomas Wayne during the events of "City of Bane." With this in mind, it makes sense why Selina felt the need to go to the extreme of stealing from a demi-goddess; it might have been the only way to prove to herself that Bruce really does love her after everything that's happened between them.
While Batman has had many love interests over the years, Catwoman has always been his main one. Not even Talia al Ghul, the mother of his son Damian, has been able to capture Burce's heart as Selina has, and the answer he gave her under the influence of the Lasso of Truth all but confirms that she's still the love of his life. Despite the many chaotic events that have occurred in their lives, Selina and Bruce's relationship is and always will be an important facet of both characters.