Title: A Potter Or A Snape

Rate: M

Pairings:

James/Lily May Turn to Severus/Lily

Sirius/Remus

Not Sure about anyone else yet

Summary: Lily doesn't know who Harry's father is, James or Severus. She'll have to wait to find out when Harry is born. Harry's older brother, Zack, is TBWL. The Beginning

Disclaimers: I do not own any of the Harry Potter Characters.

Prologue: Zack James Potter

(A.N. - I know that's Harry's middle name but for my story its Zack's since he is the first born.)

James and Lily were watching their baby boy sleep. Lily had just given birth to him five hours ago. She wasn't in labor for too long. He was out quick. Zack James Potter, Looked just like his father but his hair was a light brown.

Sirius, Zack's godfather, loved him. Sirius and Remus were over most of the time. Peter didn't come around that often.

James would spend hours playing with Zack. Lily was so happy. Her life was perfect. She had a husband that loved her and she loved him, a perfect son, and all her friends.

Chapter One: Love And A Surprise

It was October 16th. Her son, Zack, was two and a half months old. Lily was grading papers trying to get some of her work done before bed. She had got the position as charms professor at Hogwarts during the summer before Zack was born. James and Zack were staying with her at Hogwarts but once in a while they would go back home for a few days then came back not wanting to leave Lily alone too long.

James and Zack had left a few hours ago. It was Friday night and getting late. She put everything away for tomorrow and walked to her room.

A few hours later Lily was having a hard time sleeping. She got up for a walk hoping it would help her sleep when she got back.

As she was walking down in the dungeons she ran into Severus Snape. He helped her back up onto her feet. "Sorry Severus, I didn't see you there." Severus didn't say a word. He just stood there staring at her. "Well, I'll be on my way now." But before she could leave Severus grabbed her arm and pulled her closer to him until their lips met.

Lily was shocked. She didn't know what to do at first. She just stood there stiff. She couldn't think. Her brain started work again and she tried pushing him away but he was to strong. After a while she stopped struggling and kissed him back. Their kiss got more stronger, deeper, and passionate.

She didn't even relies that Severus was leading her to his room. She didn't even know they were moving. She was too into the kiss.

Severus had always loved Lily and with Potter gone he could have her, even if its just for one night. He laid her down on the bed and attacked her lips again. A moan came from Lily. "Do you want this Lily? We can stop now and Forget this ever happened." Severus was hoping she would stay.

Lily didn't speak right away, she had to think. "Yes… I want this Severus." He smiled and wasted no time. He kissed her hard. Slowly he began to remove her clothes. He wanted this to last. Lily did the same to him. They just stared at each other for a while then began to kiss again. That night they both made love not thinking about the consequences'.

Lily woke up early. The sun was just rising. Something didn't seem right. She opened her eyes. This wasn't her room. She looked over at Severus. Memories of last nights activity came back to her.

She slowly got off the bed, not wanting to wake him up, got dressed, then went to his desk to write a note. She left right after and headed toward her room.

Severus woke up feeling relaxed and happy. It was a Saturday but that's not what made him relaxed and happy, it was the memories of last nigh with Lily, the woman he loved but could never have because she was married to that damn Potter.

He sat up and looked around. Just as he thought, Lily was gone but there was a note handing on his door.

Severus,

I'm sorry but I had to leave. I know you love me and I want you to know that I love you too but I'm married to James and we love each other. We shouldn't have done what we did last night. But I don't regret it. Just please don't tell anyone. Leave it between us. I love you Severus and I always will.

Love,

Lily

Severus understood, it made him sad knowing that she did love him and they could never be together. Well, unless she left James. He would never tell anyone what happened. He loved her more than anything in the world.

Severus spent the day as normal. He graded papers, read, made potions, and ate his meals. Still he was thinking about Lily.

A Month Later

Lily woke up feeling sick. She ran to the bath room and empted her stomach into the tolet. This had been going on for a week and a half now. She was getting worried.

"Lily I think you should go see Madam Pomfrey." James was just as worried but they both had their suspicions.

"I will, after breakfast." James nodded and left to bed again. Lily got off the floor and got ready for the day. She had classes to teach.

After breakfast Lily made her way down to the infirmary. Madam Pomfrey had only taken a few minutes to check Lily. Pomfrey had a smile on her face. "Well, what's wrong with me?"

"Nothing to worry about Lily, you are perfectly fine. You're pregnant Lily." Lily smiled at the news Madam Pomfrey gave her.

"That's wonderful. James will be so happy." Then she remembered Severus and that night. What was she going to do? What if the child was Severus' and not James'. She couldn't tell anyone. She would have to wait for her baby to be born. She just prayed it was James' baby.

Next Chapter: Will be about Lily's pregnancy and Harry's birth. You will find out who his father is as well.

Ok, I hope you like it. It will get better. Please Review.

Also those who have read my other story, I will update soon.