Here's what I think was going on in Snape's mind as he lay dying in the Shrieking Shack. It's short, but I just wanted to write what he was thinking in that last paragraph of Chapter 32 in The Deathly Hallows. Hope you like it!
Disclaimer: Even though I wish that I did, J.K. Rowling owns Harry Potter.
"Look… at… me"
For a moment I saw her again. Her son's eyes so matched the precise shade, shape, and size as her own. My Lily stared down at me. The black haired boy with the lightning scar transformed into her. That beautiful red hair cascaded down her shoulders; her flawless skin seemed to shimmer in the weak light. Those eyes, how I missed those eyes. A vivid green that rivaled the leaves on the trees shimmered when she was happy and sparked when something upset her. Those eyes were my world.
I crouched hidden in the bushes, watching her swing higher and higher before leaping into the air. Concern filled me before I saw how gracefully she flew; indeed she seemed to be flying. I would hide and watch her as often as I could. She intrigued me. The girl had no idea who she was. She didn't realize that she was a witch, how could she know? Her parents were Muggles. I could not wait to tell her who she was. Reveal to her the secrets of our world.
The eyes seemed concerned, worried, and confused. Potter's face drifted back into focus, the flask filled with my last memories clutched in his hand. A pang stabbed in my chest when I realized that this was not Lily, I would never see her alive again. My fingers still pressed into the wound on my neck, though I knew that would not help. The snake had bitten deep and true.
I walked with Lily through the grounds at Hogwarts. She knew she was a witch now, and a brilliant one at that. Her green eyes twinkled more than the stars above us. I then knew that I loved her. Perhaps I had always known somehow. But how to tell her? I opened my mouth to say something when James Potter strode up, ruining the moment.
Was it so wrong to want to see her eyes one last time? My vision began to blur around the edges, obscuring most of the things around me. Yes, I was dying. I knew this and somehow I was not afraid. Not afraid for myself at least. I feared for her son, whom I was sending to his death with my memories. I tried to keep him safe for you, Lily. Oh, how I tried.
My breath was coming in shallowly; I could feel the weakness in my body. Cold was already creeping through my fingertips. The hand that was clutching the boy's shirt dropped to the wooden floor. I had not the strength to hold on anymore. I sought his eyes again, her eyes. I knew that I only had moments left and there was one last thing that I must see. To die with my Lily's eyes reflected in my own was my last wish.
One last time our eyes met. Everything was black, only her eyes still shining for me were visible. I breathed in one last time. I love you Lily. Always.