A/N: This is an AU, because a) I like AUs and b) the story I wanted to write wouldn't have been able to happen if it weren't. Also, this is doubly an AU because there is no Dark Lord and Petunia Evans will not marry Vernon Dursley.

A/N2: This is probably the only Lilybashing fic in existence. I haven't checked, but I've been reading fanfiction since early 2000 and I've never seen any.

A/N3: I will put new chapters up as soon as they're written, so don't nag. Also, this will not rise above PG-13 or T, as I cannot bring myself to write hetsmut.

The Slytherin's Guide to Dating

Step Six: Stake Your Claim

The very next day, Severus was walking up the path with a copy of The Silmarillion under his arm when a beefy young man came storming out of the Evans' house and nearly slammed into him. When he saw Severus, he turned brick red.

"You! This is your fault! You stole her from me!" he ranted.

"I'm sorry, but I think you have the wrong man. I've never gone near Lily Evans." Severus said calmly.

"Not Lily, you moron, PETUNIA!" At the sound of her name being howled, Petunia came to the door and watched with an amused expression on her face. "I'd nearly convinced her to go out with me, and then you came and took her away from me! She's MINE, dammit, and I won't let you have her! You can't just come waltzing up with- with-" he cast around wildly. "With books and seduce away what belongs to me!"

Petunia marched over and slapped him across the face. "The hell I belong to you, Vernon Dursley! And I didn't need any seducing! He's polite, he's intelligent and he doesn't babble on about how he'll inherit a drill company!" Her voice rose to nearly a shriek. "And, most important of all, he never tries to put a hand down my blouse like you did today!"

Severus went very still, and when he spoke, he spoke very, very quietly. "You did what!" He stepped closer to him. "If you ever, and I mean ever, lay so much as a finger on Petunia again, you won't be in any condition to regret it!"

"How DARE you threaten me! My father owns Grunnings, and I could have her father sacked, and probably your father as well! I could buy and sell you, you scrawny bastard!" he raged.

"On the contrary, you can't do anything to my father; he doesn't work for you. In fact, he owns his own shop in Oxford, well out of the sphere of what little influence you have. Also, if I ever hear that you're harassing Petunia again, I will report your threats and abuse of power to the police." Severus stepped back.

"You won't get anywhere with that. The Dursley name is gold in Little Whinging. Nobody will believe you." Vernon said smugly.

"On the contrary, with two witnesses saying the same thing, they'll have to believe us." Severus retorted.

A new voice intervened. "Make that four witnesses, Snape." James Potter was on the sidewalk, with Lily right beside him. "We heard what this scum threatened to do. Also, he's bothered Lily in the past, and used the same threats against her to force her to agree to it. She'll be perfectly happy to testify to that in court, won't you darling?" He looked down at her adoringly.

She glared up at him. "You promised me you'd never mention that! I trusted you!" she spat at him.

James floundered helplessly for a moment. "Lily, it's the right thing to do. Don't you want to make sure he stops using his family's influence like this?"

"No. I just want to keep out of it!" she declared.

While Lily and James were having their own little tiff, Petunia was furious.

"You unmitigated arsehole! You absolute bastard! You told me you'd never even looked at Lily!" She punched him, hard, on the nose. There was a sickening crack, and blood started to ooze down Vernon's face. He raised his hand to his face in shock.

"You bitch! You'be bwoken by nose!" He raised his fist to strike her, only to find in it a stern grip. He looked behind him, and paled dramatically. There was a policeman holding his wrist. Somebody had called the police.

"Mrs. Yvonne Polkiss called the police to investigate a disturbance of the peace. We did not expect to find you, Mr. Dursley, about to strike a woman both younger and smaller than yourself. Your father will not be pleased to hear that you have been brought down to the station again."

Lily gave the policeman a charming smile. "What do you mean again, officer? Have other girls made complaints against him?" She fluttered her eyelashes at him flirtatiously.

The policeman flushed. "No, the other two times were public drunkeness. However, other girls have made unconfirmed complaints."

Lily turned ice cold. "Then add mine and my sister's complaints to the list, and consider all of them confirmed. I intend to press charges."

Vernon laughed nastily. "Complain all you want to, slut. They'll never convict a Dursley. My father wouldn't allow it."

The policeman smirked. "On the contrary, Mr. Dursley. Your father is fed up to the back teeth with your antics, and has given us permission to prosecute you if necessary."

"I don't believe you. Dad would never do anything like that!" Vernon protested.

"Care to find out, Mr. Dursley? You have the right to remain silent. Anything you say can and will be used against you in a court of law. You have the right to an attorney. If you cannot afford one-"

"Bugger that! I'm a Dursley! Of course I can afford a lawyer!"

"Then come along then, Mr. Dursley."

The last thing Vernon Dursley saw, before the police car rounded the corner, was Petunia, his Petunia, he reminded himself, embracing and thoroughly snogging that scrawny bastard Snape, who loked very surprised indeed.