Asami honestly had no idea why she did it.
Getting over Mako hadn't been easy, but it happened smoothly enough. A few crying sessions here and there, getting drunk some nights; and when the haze of emotions and hurt had passed, allowing logic, rationality, and self-forgiveness to settle in. He'd cheated on her, then hadn't even given her the dignity of a proper breakup before calling it official with the Avatar. It wasn't exactly attractive. Or any of her fault. And so she moved on.
Which was exactly why she was so embarrassed with what had happened- ashamed, even. It wasn't that she still had feelings for him. She was, very thoroughly, over him. It was just that- well, she was feeling vulnerable. Completely, utterly emotionally vulnerable and he was right there, and it was familiar, because they both knew how to react to one another, they had an established pattern, and it was the only thing that Asami had in the moment that was safe and stable-
She was filled to the eyeballs with excuses and bullshit. Everything was falling apart. Her dad was in jail. Her company was going under. He was there. He knew how to take care of her. She went for it. She was ashamed.
Seeing him lie to Korra about their fight really was the last nail in the coffin. It was almost funny- only Mako could pull off being dishonest and disrespectful to both ex girlfriends in a few short words. It had to be a new record or something. It was wholly unattractive and he ceased to be any kind of candidate for kissing or emotional support in her eyes. Not that she wouldn't give him a shot at being friends if he apologized.
She wasn't holding her breath, though.
It was horrible that she was happy about Korra's memory returning, and breaking it off with him. It was horrible and she was a horrible friend, but Korra deserved so much better than a lovably earnest but compulsively dishonest and clueless boy. It was a breath of fresh air and she just… felt more happy for Korra than she ever had when the avatar was happy with Mako.
It was hard to explain. She just thought it was nice. The Avatar could stand to be honest with her own happiness a little more, especially with everything that was happening.
She had never had anything against Korra, despite what had happened. And when they began to talk more and become a little closer after harmonic convergence (Korra being everywhere to help with repairs and explain the portals to humans and spirits alike, Asami making big money selling various vehicles to help with the cleanup, them always bumping into each other and then planning to bump into each other), Asami had never felt so relieved. Mako or no Mako, she'd always wanted to be better friends with her.
And now, there was no Mako. Not between them, at least.
"So, when I was gone," Korra started, somberly starting the car forwards again. "Did he tell you that we broke up?"
They were driving away from the docks after they received the news, looking for the new airbender despite Mako's awkward salute. The wind blew into their hair and Asami absently noted that their acceleration was smoother than just moments before. Korra was always better at things when she wasn't trying too hard.
"Yeah," She replied, feeling her gut tense a little. "We all knew." And I still kissed him like the shitty person I am. "Sorry."
Korra closed her eyes and flushed. "That's… pretty embarrassing." Asami wanted to tell her that she, of all people, had nothing to be embarrassed about.
This was it. This was her chance. Honesty. Good friendship. Owning up to her mistakes. Taking responsibility for what she did.
"Actually, I need to tell you something about that, and, I should have told you this sooner, but, while you were gone…" It came out in a rambling rush, but she lost her steam as soon as she got to the actual confession part. Typical. She looked at Korra guiltily out of the corner of her eyes, gauging her reaction. "I kind of…" oh, get it out already. "Kissed him."
It sounded as bad as she thought it would. "I'm sorry," she added, deflated.
Korra laughed. The sound made Asami's heart jump. She wasn't mad. She wasn't hurt.
"No wonder he's so nervous around us," she said, still grinning.
"You're not mad?" Asami asked.
"No," Korra says, as if the notion is ridiculous, and Asami feels forgiven. "I mean, I kissed Mako when he was going out with you, so."
She'd forgotten about that. When Korra said it like that, it sounded fair. In a twisted way. But she remembered that Korra had never told Asami herself, when the heiress took a breath and plunged into honesty. She wasn't mad- but she still felt a bit playfully miffed.
So she put on her best unimpressed face. "You what."
She wished she could frame Korra's reaction. In one of Varrick's movers, perhaps. The Avatar looked like she had kicked Asami's puppy, eyes wide and fearful. It was cute.
"I'm so sorry!" She said, tensing up. "I thought you knew!"
No thanks to you, Asami thought, not unkindly. Again, she was over it. She relaxed, fighting the urge to laugh and feeling a little smug.
"I'm kidding. I knew a long time ago."
Korra laughed again, and Asami realized she could really get used to being the cause of it.
"Well, whatever happened with Mako," she chuckled, eyes back on the road, "I'm glad it hasn't come between us. I've never had a girlfriend to hang out with and talk to before. Except for Naga."
And the wistful smile on the girl's face really showed that polarbear dogs were great for hugs, not so much for conversation. She remembered that the Avatar was isolated since childhood and the small smile tugged even more at her heartstrings.
(Of course, a small part of her absently chuckled at Korra's use of the word "girlfriend". Normal girls using that word to merely denote female friends had been an endless source of confusion and pubescent embarrassment when she'd been in boarding school in Ba Sing Se.)
She turned and opened her mouth to say, let's go get lunch together, let Mako look for the airbender for a while-
"This is nice."
Asami agreed wholeheartedly. Then, she agreed that Korra should keep her eyes on the road.