Sometimes he remembers the red of her hair, like tendrils of sun kissed whispers sliding gracefully through his fingers. Other times he thinks of the curve of her lips when she would look at him with a kind fondness, an affection that said "you're clearly ridiculous, but adorably so."
He loves her. She's dead, but he still loves her. He just wishes that he could somehow know, somehow be told if she had ever possibly loved him, even for just a second. He thinks that if he knew this, he wouldn't mind dying. He wouldn't mind her son, he would look past it all, if only he knew that she could have ever loved him back.
Often when it's almost dusk, when the moon is just beginning to wink with it's gloating glow, he will walk through the grounds, and he will imagine that her footsteps are following him. Then they will fall into the forest, giggles and snorts, and it will be like time had never passed, and they will be children again.
But other times he just sits at his desk, his hand beneath his chin, and glares at the student who walks with her love, the boy who should never have been born, not if it had been him, who she'd chosen. Not if it was him. But it wasn't him. It could never have been him. And now she's dead. Her son got all of her love. And the man that loved her beyond all his soul, got none.
Her son giggles through class, he talks to his friends, he blows up his cauldron and his potion is a disaster. Snape is glad.
Lily's son slacks off, he makes it through, and at the end of the year his fate is sealed like it once was eleven years ago.
Snape's desk is a war zone of scribbled parchments and empty ink bottles. His students get dumber every year, just as his scotch bottle becomes more welcoming.
He keeps a photo of her in his top drawer, and on nights like these he takes it out and the salt of his tears trace delicate patterns across the sweeping smile on her face.
Sirius Black escapes, and Snape does not go looking for him. He leaves behind a lot of things in life, like lost chances, a love beyond the length of his fingertips, and a boy with a jagged scar on his forehead.
Her son will die. One day he will get himself killed. And Snape won't know if it'll be Lily's eyes looking out at him from a pale face of death, or those of a boy too like his father to stand a chance.
Snape watches as her son defies laws, fights dragons, and survives another year. Snape drowns eternal nights in tasteless scotch, frowns at every student he passes, and gives a year worth of detentions.
He dreams of tousled hair and glowing eyes. It isn't her though. It's him, it's her son, and Snape wakes with a cold sweat and an unwavering burn in his left forearm.
In the morning his boots clack against the cold stoney corridors. He rounds corners, the blackness of his robes billowing into formless shadows, and he comes across the Malfoy boy, his cronies pinning her son against the wall.
Potter looks trapped, grey in the face from the elbow at his throat, and Snape reacts. His arm moves and his wand rips into the air. The three attackers scamper, and then it is just him and Potter.
The boy glares at him, and it stabs into the strings which hold his heart together, because he sees her eyes, and a hate that he shouldn't deserve.
Obsidian and green both move to the fallen wood of Potter's wand, and a scowl forms between Snape's brows before he has a chance to alter it.
Snape starts to speak, his mouth dry and unwilling.
But Potter's gone. He picks it up in a flash of humility, and flees. The boy is his father, and Snape walks away trying to convince himself of a battle he'll one day surely lose.
The boy has no one. His two friends are but two tag-alongs who know it's too late to back out. Snape knows this because he was once like that himself.
He watches as Potter's classmates turn away, like he is a liar in a world that is against him, and Snape refuses to acknowledge the familiarity that burns in his chest.
Snape reads over Potter's essay. It's terrible and his writing is nearly illegible. Snape chokes down more scotch, and marvels over the loops of the y's, and the crossing of the t's. The letters haunt his dreams, and when he wakes he hastily marks the crinkled parchment with a fail.
The job he's always wanted is his, and the students hate him for hit. He suspects Potter is among them, because the boy's eyes dig into his skull throughout the entire first lesson. Snape doesn't put a name to the heat along the back of his neck, or the desire to leave a firm imprint of knowledge in the young mind. He lost that chance five years ago.
The boy uses one of Snape's own spells on Draco, and the man stares at the son of his once beloved, disappointment heavy in his gut. They look at each other across a bathroom splashed with blood, and it reminds Snape of the night he first saw Potter, the night where he held the boy's dead mother in his arms.
Dumbledore falls from a tower, and the boy's hate overwhelms him with a dangerous clarity. Potter follows him through the night and over the sharp and treacherous bramble of the forest. Spells are flung at him with the despair and haphazardness of a boy in pain, and Snape wants to turn around and shake Potter's thin shoulders, to tell him the truth.
But instead he just keeps running.
He hears about the boy's travels, about the dangers feats he accomplishes, and Snape doesn't know whether to laugh or cry.
He goes to the woods, the cold silver of the sword hitting his thigh, and he watches the boy he must now admit is a man.
Blood clots his throat and clouds his vision, but he still sees, still knows, that green eyes, her eyes, stare into his own with an intensity he now knows he deserves.
It isn't her though, it isn't Lily, and maybe it never was. Maybe a hidden part of him always meant to protect, to do the impossible for a boy he should despise and want dead.
But Harry Potter is a boy who grew up in a war, and Snape understands now, he realises what he should have felt in the first moment he caught site of that scar, he realises that love is something Lily would have wanted him to remember. To keep safe and to cherish.
Snape's hand finds the boy's cheek, and his lips form shaking words he'll never be able to recall, and then he goes.
He dies with a love that greets him the last second, and he clings to it.
Snape dies a proud man.