Lucius Malfoy and Severus Snape through their schoolboy days and adult lives. Mostly platonic. This is probably the closest Slytherin version of the Marauders-type friendship I can get.
Snape
As far as first impressions went, Prefect Lucius Malfoy was not impressed in the least by the crop of first years joining their table. He knew several of them by their family name, if not by sight. Avery, Carrow, Selwyn… Pureblood society was narrow enough as it was. Eyebrows were raised when Sirius Black was Sorted into Gryffindor. Angry mutters swiftly silenced with a glare from Narcissa. It was her cousin who got Sorted away after all. Sirius was always a rebel, so the whispers went.
Snape. A non-wizarding name. A dour, pallid youngster, too thin and nursing a bruised cheek limped to join them, uncertain and as gangly as a new colt. His robes sat a size too large on his thin frame, likely secondhand castoffs. His dark eyes warily drinking in his surroundings, as if he had never seen magic of such scale before. For a moment, Malfoy wondered if the Hat had tossed some hapless Muggleborn their way. It had happened before. They never lasted long in that nest of vipers. Somehow, he ended up on the end of the bench next to Lucius after failing to find a space anywhere else. Lucius greeted the boy with a smile and passed him the pumpkin juice. One had to make the first-years welcome after all.
Severus Snape. Half-blood. Dirt-poor, only son of a tyrant of a Muggle father and his much-abused magical wife. Lucius would learn that much later.
Slytherins were quick to form cliques. Family names and ties, charisma, and wit - all forming unspoken partnerships against the world. By week three most of the first years had a friend or two in their year to attend classes with. The more popular children had entire entourages like some medieval royal. Such had the pleasure of selecting and discarding their acquaintances. Some might seek alliances with their seniors or across Houses. Lucius had gone through the same in his lower years before whittling his friends to a select few, though he still maintained a cordial relationship with the scions of families his father deemed necessary for their social standing.
There was one boy who went against the norm. A lone wolf – the solitary Severus Snape.
He kept to himself in a corner of the common room, almost invisible amidst the hijinks of his housemates. Often, he would be poring over some old textbook or scribbling notes. He haunted the library too, alone and half-buried behind stacks of books.
When Lucius noticed, his curiosity was piqued. A lone student was easy prey for bullies, especially if they wore Slytherin colours. Snape soon attracted the attentions of a gang of Gryffindors, among them Sirius Black. In his fifth year, Lucius had his Prefect duties and OWLs to worry about. One of those duties involved deducting points from miscreants, especially those who picked on his younger House mates.
"He fancies that Evans girl," Narcissa nudged as they watched the boy weave among the students crowding the lower corridor to walk beside a red-haired girl weighed down with an armful of books. "Pity she's a mudblood," Rosier snickered, just before Potter and gang came hollering and running, knocking a hapless Snape down a flight of stairs as they passed.
No, Snape sat with his redhaired playmate in the library or in quiet corners of the castle, or by the Black Lake. He would contrive to be paired with her for Potions or whichever classes they shared, so the common room gossip went. Puppy love, Narcissa cooed. Lucius would roll his eyes.
"She's my friend!" Snape was quick to defend her in the common room against some outraged third and fourth years.
"She's a mudblood. You shouldn't even speak to her."
"She's a Gryffindor. We do not make friends with Gryffindors… She's stuck-up, ugly, and stupid like the lot of them!" Someone shoved Snape hard enough for the smaller boy to stumble.
Pulling himself away from his books, Lucius was forced to wade into a brewing fight before wands were drawn in the common room. The more boisterous troublemakers then filed out at someone's announcement that there was a Hufflepuff birthday party in the Three Broomsticks to be crashed. Snape remained behind. The damage had been done. He no longer had the heart to continue poring over his notes. Perhaps a game of chess would settle his mind.
Lucius had no desire to mingle with any Hufflepuff - ugh. Narcissa had gone home before term's end to attend to some pressing family matters at her parents' insistence. Avery and Rosier were serving detention for blowing up someone's cauldron in class. The studious fourth-year student who might have been a worthy chess opponent announced his intention to retire for an early night. That only left Severus Snape, first-year.
"Do you play chess?"
Snape warily nodded. His eyes too dark in his pale face. He was shrunk up against the corner nearest the bookcase.
"Good, come over. I need a game. I will not bite!' Lucius laughed carelessly. Snape slid into the chair across him from the chessboard. The chess pieces were already assembled in expectation of a game.
"White moves first…" Severus ventured after waiting for his senior to make his move. Everyone knew Malfoy always played white.
"You start. I'd play black for a change…"
Without even knowing it, the Slytherin prince had taken his younger halfblood housemate under his wing.
His father would have a fit. Severus Snape was a nobody.
Severus was smart, well above the average student his age. He shared little about his family life apart from what Lucius had already picked up on. The Malfoys understood what appearances meant. Control. Masks. Be strong. Shut away the pain, the hurt, no matter how much your heart's bleeding.
Lucius and Narcissa had an understanding born of duty to their families. She was the fairest among her sisters. Thank Merlin it was not Mad Bellatrix he was saddled. Had he been the luckless Roddy Lestrange, a dive into a manticore's maw might be preferable. By his fourteenth year, Lucius had accepted that he might grow to love Narcissa someday. Whatever love meant.
His parents separated after his birth. He heard his mother had discreetly entertained a close female friend in Italy. It was part of the marriage contract drawn between their families. Once the required pureblood heir had been produced for Lord Abraxas, her part was done. On paper, his parents remained wed, even though he had not seen his mother since his fourth year when she left Malfoy Manor for the last time.
Abraxas was stern with his son. Everything must be perfect. He had derided Lucius as weak when in his third year, he ended up on the wrong side of a Bludger and broke his hip. His father had railed at him for his spectacular and disgraceful accident. In front of the school's board of governors, and what was all the screaming business about? He was secretly relieved when the healers declared he should not play Quidditch again. His interests ran to a more scholastic bent even if he was not averse to a good duel.
They had played until Snape was almost drowsing in his seat. Midway through the game, Rosier and Avery stomped in complaining about their detention and headed for their beds when they saw Lucius was in no mood to listen to their griping. Finally, Malfoy's queen knocked Snape's king off the board. Lucius declared the game over and congratulated the sleepy boy on a game well-played. Snape pulled himself back to his dorm for a well-deserved rest while Lucius settled down to a nightcap of brandy before the rabble returned from that Hogsmeade party.
Author's Notes:
Hope I can write the development of this Slytherin friendship in a believable way. Lucius is about four years older than Snape.