I know there's a lot to criticize Lily for, but do you have any fun/cute headcanons about the Snily friendship? I don't think it was ever completely healthy, but I do think there's plenty of room for some cuteness in that dynamic, especially before Hogwarts. I like to think they used to spend a lot of time in Lily's room listening to music, and bantering and trying to convince each other about their different music tastes.
Oh, I do think snily friendship was pretty cute, even if codependent. They clearly spent some time at her place, and she was aware enough of the situation in his household to be concerned, so I hc she helped him to deal with his bruised hands and face a couple of times, like took an ointment in secret from her parents' medical kit, and they pretended it was a potion to make it all a bit better.
Spending time with her, Severus would have access to things not available to him at home – like a music player, actually! Would Snapes even have a radio, if they couldn't afford a shirt for their son? Where would Severus listen to popular music before he met Lily? It had been Lily who introduced him to it – and he tended to agree with her music choices initially, but after some time, figured out that his taste is actually quite different from hers.
I also think they role-played as wizards a lot, lol, like were running around with sticks and using branches as brooms and made potions out of grass and bugs. Severus took some of the magic books he had to read with her, probably even the textbooks – so Severus and Lily both impressed the teachers with knowledge on their first year!
They'd also totally gossip about Petunia and try to piss her off. Like, they sneaked into her room! They couldn't know about the letter then – Severus could've seen it only if they already were inside, so they did it for fun, or maybe to give her some petty trouble. After all, Lily did turn teacaps into rats in front of Petunia on her vacations, didn't she?...
I don't think that the Evanses approved of their friendship, judging from Severus staying far away from them during the Platform scene and Petunia's derogatory comments on his family, but he'd still probably get some treats (he'd savour every bite) and maybe stay for a dinner a couple of times, and they'd be perplexed that this feral thing has some kind of high-class manners showing sometimes. Other times, he behaves like a total gremlin, tho.
Lily gifted Severus the flowers she magically made bloom, and he kept them as a herbarium in one of his books. He still has those as an adult.
Severus always was stressed before the holidays, because he didn't know what to gift Lily – he didn't have money for anything. So he tried to make something himself – draw her a picture, or bring her wild flowers, or make a secret hideout house out of branches and leaves for her, or create "magical" amulets out of stones and pebbles. When he was a teen, as soon as he started to make his own spells, he created one that made lilies grow and gifted the spell itself to Lily.
When Severus was at her house, he spilled something on his blouse, and they had to handwash it and put it outside to dry for a bit. Lily gave Severus one of her dresses while they waited, so that he didn't sit there naked. He was really shy, but she thought he looked very cute in it.
Lily kept a tiny notebook to write the magical words Severus taught her with her own definitions and illustrations. She drew sparkles and little stars near all the spells. Petunia once found it and made fun of her, so Lily stopped writing in it.
They had a game where they planned which new potions and spells they would invent when they went to Hogwarts. Severus said he’d invent a potion to make Petunia nicer. Lily said she’d find one to make Severus' father calmer.
When they fought, Severus always came to apologise, so Lily had been used he'd always reach out after an argument. He tried to remember what upset her and not repeat the same mistake again – because he had known that's what his mom does to not upset his dad.
