I see all your ‘Kara is jealous of Reign’ headcanons and raise you-
While Lena and Kara are just realizing that there just might be something between them, Lena meets (or reunites with?) Samantha March and they become very close very quickly.
But when Lena gushes to Kara about her new friend and her new friend’s cool daughter (à la the lunch scene in which Lena expresses her excitement about her relationship with Rhea) Kara has a serious but unreadable look in her eyes that confuses Lena.
So their inevitable meet up puts Lena on edge, and the internet boards in response to “Friend acting weird about other friend??” that propose jealousy as the answer may make Lena excited about the possibility of Kara having feelings for her, but they also do nothing for her nerves regarding this predicament.
So she puts their meeting off for quite a while.
Eventually, to her surprise, Kara is the one who insists on meeting Samantha, proposing that the three of them go out to dinner for Lena’s birthday. Having already agreed to dinner with Kara that night, she can’t exactly say she’s busy. And she can’t say that she’d prefer it to just be the two of them, because that’s dangerously close to admitting her feelings for Kara.
So she reluctantly agrees.
When the date arrives, Samantha is waiting for the at their table, and when they reach the table and Samantha stands up, Lena’s heart practically ceases beating for the few seconds Kara and Samantha look at each other, silently.
And then Kara simply puts her bag down, walks directly up to Samantha, and gives her a
not as crushing as it rightfully should be hug, to both Lena and Samantha’s surprise.
(Meanwhile, Samantha throws a “you weren’t kidding about this girl” look to Lena over Kara’s shoulders)
And as it turns out Kara is just??? so grateful??? that Lena has another close friend who gets how great she is??
She was kinda tentative at first, because Lena became so attached to her friendship with Samantha so quickly, but the more she heard about her, the less she was protective and the more she was just kind of calmly proud and happy for Lena.
And so they hit it off seamlessly. It’s not twenty minutes in before Kara invites Samantha to game night.
(“Wait…Am I invited?”
“Hahaha Lena, I had Jess slip it into your schedule weeks ago, silly.”
“So that’s how you manage to get her away from L-Corp. I’d been wondering what I was doing wrong.”
“Yeah, that’s part of it. But sometimes I just kinda smile at her? And she does what I want? So you could try that, too.”
“Uh… haha I’m not sure that’ll work for me.”
“Hmm? Why not?”
“UM WOW LOOK A THE TIME IT’S BEEN LOVELY BUT IT’S TIME TO GAY- GO, GOo IT’S TIME TO GO” )
And so the three of them end up doing a lot of hanging out, and Samantha manages not to feel like a third wheel
most of the time. And Kara’s happy to see Lena with a support system in National City that goes beyond just Kara and her friends.
So when the time comes that Samantha needs them, when Reign begins to overpower her mind and make her target Supergirl, it’s Lena and Kara who work together to bring Samantha back to herself.