tiny, you have been reading too many fanfictions.
::wipes a tear of mirth from her eye:: hooboy did I laugh at that. no offense, but Snape didn't have a thing for Lily. It's just not physically possible. If you ask me, if Snape liked a person, people would know about it.
Well, because I am feeling mad at certain people today, I will redeem myself by tellling you what I either KNOW or think.
for one thing, I can honestly tell you, as a mean person myself, that if there is any reason AT ALL why Snape is mean, it's because he just generally likes being mean. For some reason, we all get this sick sort of pleasure from lording anything whatsoever over EVERYONE. But of course, I belive Snape has his limits, as do I. Snape DOES remember what it was like to be teased, most likly.
Tha might be another thing. He might just be making up for his childhood, though I personally would feel ashamed of him if that was the reason. "Couldn't you come up with a better reason Snapey-poo?"
"Nah, sorry. I guess those slimy things I ate for breakfast must have made my mind a blank."
"Yeah, they do that sometimes."
But, anyhoodles if Snape must have several reasons for being mean to Harry inparticular. For one, there is the jealously facotr, which makes Snape jealous of Harry, because he sees how, even though he led a young life of ignorance and beatings, he still managed to become somewhat popular and respected, whereas Snape himself was called a slime-ball.
Then, there is the parental facotr. From what we know, Snape and James did not get along, to say the least. And I guess it didn't help that SIrius was James' best friend. The jealousy facotr counts in this instance too.
Then there is the history factor, or, as I like to call it, the greedy-bastard facotr, which has always proven to be so cheerful in the past. Snape, from what we know, was somewhat important in VOldemort's plan for the future. Then, he got caught, and was realesed on a trust. I feel that somehow the factor of Harry fit in there. A personal theory of how just popped into my brain, and feel like spewing it out now.
Here goes: Voldemoprt was relaying his plans to kill Harry and the Potters to SNape and several others. Because James had saved Snapes' life, and somehow, Snape still didn't want anything bad to happen, he argued with VOldemort, therefore getting himself in trouble. He got kicked out of Voldemort's lair, just barely alive, when Dumbledoer found him, and used him as a spy. Snape, who had been becoming quite prosperous then blamed Harry for his own demise. The ACTUAL reason Snape protected harry in the first book, was because, for some terribly trite reason, he had a tiny, little, bit of love (which made him "hate" harry all the more) for Harry, because ::breathe:: he knew that he was being stupid, and that being kicked out of Voldemort's little group had saved his life!
"Missy Feather? Why is that vein sticking out of your forehead?"