"What the hell is she doing here?" my sister Jean demanded. Lupe and I jumped apart in surprise. We'd been sitting on the loveseat in the living room. I had Lupe down to just her panties. I still had my pants on. As you might have surmised Jean's arrival was completely unexpected. She was supposed have been out all day. My parents were out of town for the weekend and I thought I'd been clear to invite Lupe over for a little heavy petting and maybe if I got lucky I'd lose my virginity too. Lupe's a classmate of mine.

"Answer me!" Jean demanded again. "You're in so much trouble when Mom and Dad find out about this, having the school's biggest slut in our home."

"Give me a break. I'm not the school's biggest slut," Lupe said finally. "I'm probably not even in the top 50 among school sluts." She stared back at my sister defiantly. "As far as what we're doing, if you're not sure, maybe you should stick around and watch. Perhaps you'd learn something."

Jean blushed deeply and said, "I don't care what your slut ranking is, bitch. If you're not dressed and out of here in the next 30 seconds I'll pull you out of here by your hair just as you are."

"I'd like to see you try."

"Uh, maybe you'd better go, okay Lupe?" I said. I was already in deep enough shit without Lupe adding to it. I was already resigned to being grounded for the rest of my life and I'm only 16 years old. My name is Tim.

"You'd better listen to Timmy, Scarface. You're now about ten seconds away from me tearing into you." I cringed. Lupe had a thin scar along her left cheek about an inch and a half long. Scarface was her nickname but only behind her back. Rumor had it she acquired the scar in a fight with another girl over a guy but I'd never have the guts to ask her about it. Lupe's olive complexion turned darker with anger.

"I feel sorry for you, Tim," Lupe told me calmly, "with you having this sister who's already acting like an old maid." My sister cried out in rage. She grabbed hold of Lupe's hair and yanked my friend out of the loveseat. I was really surprised. I'd never known Jean to be the violent type. She must have been having a really bad day. Lupe responded with her own cries of pain and rage. I thought it would be over pretty quickly. Jean had taken Lupe by surprise and also had a 20-pound weight advantage and a three inch height advantage on my guest. I valued my own physical safety so I didn't try to interfere. I did, however, station myself in front of the door. I wasn't going to allow Lupe to be thrown out half-naked.

The next thing I heard was Jean's own cry of pain. She let go of Lupe's hair and clasped her boobs. Lupe had obviously sunk her nails into my sister's tits. Lupe quickly took advantage of the situation by grabbing Jean's hair and pulled her backward and off balance. "Help me!" Jean cried.

"Keep out of this," Lupe warned me. "This is between her and me." She gave an extra hard yank on Jean's hair and my sister fell flat on her back. I think the wind got knocked out of her. Lupe quickly bent over the defenseless figure and ripped open her blouse. Buttons went flying. Jean's bra went next exposing her tits. This was amazing. I'd never before seen her tits; not that I hadn't tried on occasion. Jean was 18 and had always been a pain in the ass to me for as long as I could remember. Now I thought I could get something on her so she'd leave me alone. I ran to my bedroom and retrieved my digital camera. I returned and started snapping pictures. I had a hell of a woody going. Lupe didn't seem to mind. "Good idea," she said smiling. Jean regained her breath about then.

"No, Tim!" she screamed and covered her exposed tits with her arms.

"Put your arms down or I'll hurt you again," Lupe warned. Jean looked at her and saw that she was serious. She looked over to me as if pleading silently. The tears coursed down her cheeks but I didn't feel sorry for my sister at all. She'd brought this all on herself. Slowly, Jean dropped her arms and I snapped another picture. I could see red marks where Lupe's nails had dug into my sister's boobs. I could tell there'd be bruising soon. "I beat you fair and square, right?" asked Lupe.

"Right," Jean admitted grudgingly. She watched Lupe retrieve her shorts and reach into the pocket for something. I couldn't see what it was but Jean did and she yelped in fear.

"If I had my knife handy when we fought I would have cut you good for disrespecting me," Lupe said displaying a four inch blade. "I still might do that."

"No, Lupe!" I blurted. This was now out of control. I didn't want my sister disfigured. Hell! I didn't realize Lupe might be armed.

"This was for you if you tried to rape me," Lupe said to me. "I can still use it on you if you try to interfere." I gulped and kept my mouth shut but thanked my lucky stars for not getting pushy with this crazy girl.

"Please don't cut me," Jean begged. She began to sob as Lupe placed the flat of the blade against her cheek.

"Why not," Lupe replied. "You could discover the joys of being called Scarface just like I have."

"I'm sorry I called you that," my sister blubbered.

"It's too late for sorry, sweetie. Now you have to pay for your disrespect. So which cheek would you like it on; right or left?"

"Please don't do this, Lupe," I begged. "What happened isn't worth ruining her life and yours."

"Well, she could be my bitch. I might consider that. Would you like to be my bitch?"

"Yes," Jean blurted almost in a panic. "I'll be your bitch." I'm sure Jean didn't know what being Lupe's bitch meant but it had to be a lot better than being disfigured.

"Good answer," said Lupe. She stood up and took off her panties. Jean and I both gaped at Lupe's naked body; I'm sure for different reasons. Jean was apprehensive about Lupe's intentions. I was just admiring the girl's body. I'd seen plenty of women's snatches in pictures and Lupe had the hairiest one yet. She looked like her tits were bigger than Jean's but I think it was because of Lupe's smaller stature overall. "You're going to eat me out to show your devotion to me," Lupe announced.

"I-I won't do that," said Jean. The horror she felt was apparent in her voice.

"You won't do it?" Lupe asked. "Is that what you said, Scarface?" She waved her blade in front of Jean's face.

Jean gulped and said, "Not in front of Tim ... please!"

"Oh, yes in front of Tim," Lupe replied. "He has to take more pictures. I want plenty of evidence so you don't go thinking about getting revenge on me. These pictures would look very nice on a web site, don't you think?"

"I won't try to get revenge," Jean wailed.

"I don't think you will either but we're going to do this anyway just because I want it." Lupe straddled Jean's prone body and slowly lowered herself on my sister's horrified face. "You'd better be enthusiastic with that tongue of yours," Lupe warned. "I'm not going to let you up until you get me off three or four times." I heard Jean moan in despair as her face disappeared underneath Lupe's snatch. Lupe moaned in pleasure and I could only assume my sister was carrying out her undignified task. "She's pretty good if she's a beginner," Lupe added. "Why aren't you taking pictures?"

"I uh ... well, you can't see her face so what's the point?" I'd forgotten I still had the camera. I wished I hadn't brought it out. What plans did Lupe have for the pictures? It couldn't be anything good? What if I erased the pictures? Would Lupe be after me for disobeying her? I didn't want to be known as Scarface either. I continued fretting about my dilemma until Lupe finally stood up.

"She only got me off once but I think she'll improve with practice," she said conversationally. The girl wasn't self conscious about her nudity at all. Lupe was definitely a beauty even with her scar. She looked at me and then pointed imperiously at Jean. I snapped another picture. I instinctively realized this is what she wanted. Damn! She was training me too. "Get up," she ordered Jean.

Jean was slow to get up. She appeared to be in a daze but she did her best to obey. No sooner had she risen but Lupe ordered her to finish stripping. "My bitches don't wear men's clothes," Lupe declared referring to my sisters slacks. Jean's resistance was gone along with her spirit. She gave me a look of pure misery and unsnapped the fastener at her waist. Strands of Lupe's pubic hair were pasted to her mouth. I snapped another picture as she stepped out of her panties. Once completely naked Lupe ordered Jean back down on her knees and I snapped more pictures with my classmate posing triumphantly beside her slut.

Lupe motioned me to come nearer and I obeyed. She reached for my belt and unbuckled it. "It's time you got comfortable too," she said. I didn't resist and I soon found myself completely naked like Jean and Lupe. Jean looked kind of nervous as my stiff prick popped into view. "Isn't your brother's prick pretty?" When Jean didn't answer Lupe she said, "I asked you a question, bitch."

"It's pretty," Jean said quickly taking note of Lupe's menacing tone.

"Is this the first prick you've seen?" Lupe took hold of it and started fondling it. I felt like I was in heaven.

"No, it isn't."

"Then you have a boyfriend, is that right?"

"I-I just broke up with him," my sister replied with a catch in her voice. That was news to me. I didn't realize she had a boyfriend to break up with.

"Oh, that's too bad. Was he anyone we know?"

"He doesn't go to our school. He's ... older."

"I assume you fucked for him so you're not a virgin." Jean blushed and nodded her head.

"It's your turn," Lupe said. I wondered what she meant by that but Jean seemed to know. She stood up slowly and reached for my prick. I gasped as my sister's hands replaced Lupe's and began gently stroking me. I was certainly surprised but very pleased.

"Oh, gosh," I gasped. If I this kept up much longer I was going cum hard in someone's hand. Jean looked at me without resentment and I was glad for that.

"It looks and sounds like Tim is enjoying himself. Are you enjoying yourself, Tim?"

"Yes," I said only. I couldn't lie.

"Why don't you let Tim fuck you?" My prick lurched in excitement. Jean and I both stared at Lupe in amazement.

"I can't do that," Jean protested. "He's my brother." Whether purposely or not my sister began to stroke me more vigorously.

"Brothers and sisters fuck all the time," Lupe replied. "I know that for a fact." I didn't ask Lupe how she knew this but it made sense to me. I'd fantasized about fucking Jean in the past and she was now buck naked and stroking my prick. I knew I'd do it if Jean was agreeable but I didn't want to force her. I wanted a willing partner.

"I don't want to get pregnant."

"Most of the thrill of fucking for a girl is knowing she's taking the risk of getting knocked up," said Lupe. "I can't get off without it. I guess your boyfriend wore a condom, huh?"

"That's right."

"Well, your brother wants to fuck you and he wants to do it bareback. Am I right, Tim?" I didn't answer verbally. Instead, I responded by shooting a stream of my load. Jean shrieked in alarm and jumped back when it landed on her belly. The second and third streams went wild. Most of it landed on the floor but some of it landed on Lupe's thigh. "I guess you have your answer," Lupe added with a giggle. "Don't wipe it off!" My classmate scooped up the scum she had on her thigh and looked at it with a frown. "I hate to see good sperm go to waste, don't you? Spread your legs!" Jean started to protest and then thought better of it. Lupe still had that blade. My sister moaned in fear as Lupe began working my cum into her snatch. "Who's your new boyfriend, bitch?"

"Tim?"

"You're right on the first guess." Lupe moved behind Jean and pushed her into my arms. My prick responded by slowly standing to attention once more. My sister had to feel it stiffening between us. She looked frightened but didn't pull away. I was kind of frightened too but that didn't seem to affect Mr. Stiffy. "Go ahead and fuck her," Lupe said. "You wanted to get laid today, right? Now's your chance."

"I, uh, better not," I replied. Yeah, I wanted to get laid but with Lupe, not my sister. My parents were going to kill me for just what happened so far if they found out.

"Well, how do like that, bitch? Your brother just turned down a chance to fuck you. If I didn't know better I'd think he was gay for turning down free pussy, wouldn't you?"