Bruce Wayne is Gotham's most famous billionaire philanthropist. As Batman, he is Gotham's greatest detective and heroic vigilante.
Selina Kyle is Gotham's fund manager and charity fundraiser at East End. As Catwoman, she is Gotham's wanted cat burglar.
When Catwoman, however, saw Batman for the first time, it made her drop her bag full of stuff she stole, and her jaw dropped at the same time. It also made her think that he is the world's most expensive jewel all because he was tall, dark, handsome, and, most importantly, the man of her dream.
Even since Selina out of her Catwoman costume, went to sleep, she usually dreamt of seeing a mysterious man in a suit with an appearance of a bat leading people, including her to safety from a terrorist attack on Gotham's tallest building, Gotham Tower.
Selina felt thankful for him, but she didn't know why she had that kind of dream most of the time. She thought maybe it's because he looks like her as Catwoman. Suddenly, she felt the urge of liking her dream. She had been wanting to see him or meet him in real life someday all because she felt sad and lonely due not having anyone to live with but her nine docile and loving cats.
Not long before Catwoman saw Batman, she once saved a young, innocent girl from being raped by gangsters. After that, she felt like she was a hero to her herself and she agreed but she was still a thief. She heard many times about Batman is that he is Gotham's most dangerous and intelligent vigilante other than a tall, dark and handsome man.
She took responsibility to return all the things she stole to Batman's most helpful and trusted assistant, Commissioner Gordon, and apologize to him before he sent his units to return them to the rightful owners.
Two nights then, Catwoman meets Batman and flirts with him so she can have a relationship with him. She asked who he was behind his mask, but he told her to introduce herself first, which she did, including her true identity behind her mask. Batman knew who she was in her Catwoman costume after she introduced herself to him.
Batman didn't introduce himself to Catwoman because he was afraid that anyone crazy about him, especially her, would tell everyone. Not only that, but he completely disregarded her because he was tired from his fight with the gangs that night and wasn't ready for a relationship.
Months earlier, Bruce Wayne out of his Batman costume, had once met Selina Kyle at Gotham's Central Charity Ball. Selina talked to Bruce first because he looked so handsome and had a strong jawline that can make a woman's heart stop.
Despite Bruce's helpfulness and kindness with his job, Selina became interested in him without knowing his superhero identity. She had asked him to go out with her, but he refused and disregarded her due to him being busy with his job all the time.
On a rainy night that turned out to be a failure when Bruce as Batman was going out on patrol, Dr. Jonathan Crane/Scarecrow fear-gassed him and lit him up. He had survived but was exhausted. A horrified Selina as Catwoman came over and took him into her apartment for minor recovery and comfort. Bruce still felt like he wanted to disregard Selina but he thanked her when he woke up. He owed her apologies for disregarding her and explained to her why.
After that, he revealed his true identity to Selina, and she was surprised to see that it was Bruce Wayne, the man who she was interested in combined with Batman, the man of her dreams. Selina asked Bruce if she can join crime-fighting with him because she is afraid he will end up getting hurt, especially what Scarecrow just did to him. Due to Bruce's solitude, he said that she is free to join him.
In the story, Bruce and Selina will start a relationship, and it'll gradually evolve when they are doing their acts of heroism and vigilantism together for a while. They'll both become Gotham's crime-fighting duo and lovers while they are in a healthy relationship. Their relationship is going to be romantic on the outside but sexual on the inside.