When Lena comes to Hogwarts many people don’t see anything beyond her family’s legacy (Lex was a notorious dark wizard) and when she is sorted into Slytherin everyone thinks she is going to follow in their footsteps.
Everyone except Kara Danvers, who understands living under your family’s shadow.
She is related by blood to Kal El, the auror who finally defeated Lex Luthor. But her birth family was killed during the war and she prefers not to tell anyone the truth in fear of not being able to uphold her family legacy.
Kara sees Lena studying alone in the library one day and decides to go over and talk to her.
She is hostile at first, thinking that Kara is just another person trying to make fun of her but as soon as she sees that earnest and bright smile she knows Kara is different.
They soon become good friends and Kara always stands up for Lena whenever anyone mentions her brother.
Lena is the cleverest person in the school and she loves to help Kara with her homework and any spells she found tricky so the two of them are often see in the library together.
Alex is wary at first and tells Kara that being friends with a Luthor is a bad idea but Kara is determined to prove her wrong.
Slowly people stop behaving coldly towards Lena, because Kara is the purest person in the school, so if she likes Lena then she can’t really be that bad.
Kara wants to tell Lena her secret and she almost does many times but she’s scared that if she did Lena would stop liking her because it was her cousin was the one who but her brother in Azkaban and despite everything Lena did love her brother.
One night when they’re up late chatting in the Slytherin common room she finally decides to tell her.
Lena just hugs her and cries, because Kara had always been understanding but she never realised quite how similar her and Kara were.
They talk for hours that night about their families. Kara talks about what her life was like before her parents died and Lena tells stories from before Lex turned to darkness.
They both fall asleep in each other’s arms and wake up tangled up in a blanket together. Kara has to sneak back to the Hufflepuff common room before she gets into trouble.
These midnight talks become a regular occurrence and they almost get caught more than once but thanks to Lena’s quick thinking they avoid trouble.
In 5th year they are both made prefects and are absolutely over the moon and send each other excited letters as soon as they find out.
One night, when they’re particularly stressed before OWLs, Lena decides to take Kara up to the astronomy tower.
She points out all the stars and constellations she used to love as a child and Kara shyly admits that she always just made up her own and points out to Lena some of her favourites.
Lena can’t stop thinking about how cute Kara looks as she talks about them enthusiastically.
“Can I kiss you” she asks without thinking. Kara looks surprised.
“Kiss me?” she squeals. She doesn’t say anything more and Lena’s heart starts to beat faster, suddenly worries she did the wrong thing.
But then she feels Kara’s lips against hers and it’s the best feeling in the world. They both go to bed that night in total bliss.
With all of the exams, they don’t get to tell anyone until the exams are finally over in the summer.
Everyone goes out on the grass to celebrate finishing exams and much to the surprise of everyone Kara and Lena kiss.
Alex and Maggie do the same (although with the way they act around each other that wasn’t really a surprise to anyone).
Word travels around the school fast and soon they get many people congratulating them. There are a couple of snide remarks about how Kara shouldn’t be dating a Luthor but most people are happy for them.
For the next two years at Hogwarts their relationships continues and by the time they finish they are like family to each other and settle down in a nice house somewhere in the countryside where they can go outside and look at the stars and think of their first kiss.