This was the most humiliating day of my life. My brother's girlfriend swapped bodies with me so I would lose her virginity for her. While I was on my knees sucking my brother's dick, I could hear her in my room, banging my girlfriend away.
"That's amazing baby. If I didn't knew I would think you were not a virgin but a slut. It's like your life depends on sucking that dick!" I could hear my brother say. Actually, my own dick depends on this. If I don't do a good enough job his girlfriend will leave me in her body. I don't want to spend the rest of my days with a pussy between my legs!
"Okay, I can't take anymore of this, let me do you" he said. I got up and laid down on the bed, awaiting my fate.
"Hm somebody got horny sucking dick!" he said. I lowered my hand and felt the alien sensation of having a void between my legs. And yes, I was wet. That made me even more embarassed.
"You don't have to be shy baby! You're a woman, it's natural to enjoy a dick!" he said, which embarassed me even further. "Ok, let's take it slow" and he aligned the head of his dick with my pussy.
That thing is huge! I felt like my whole body was being worn like a glove! He went slowly until he reached a stop. "Ok baby, ready? Here it goes" I just nodded, I couldn't look him in the eye. And he went.
"AAAAAaaagh!" I screamed at first, but it turned into a moan. He thrusted and took it a bit out, proceeding slowly. Until he got the whole dick into me. Then he stopped. "You okay baby?".
I couldn't look at him. This felt too good! I was being filled by my brother's dick and I loved it! So I just said into his ear "I love it, keep going" and he did.
I felt like I was being split in half, like my body was being completely filled, it was too good! I couldn't face the thought of looking at my girlfriend after enjoying this so much. My brother kept pumping away, until he got tired and asked me to ride him. I didn't move, I was still dealing with it all, so he put me on top of his dick and kept pumping.
That woke me up! Shit, it feels even bigger this way! I looked down in amazement, I still couldn't believe that pussy being filled belonged to me! And while I could feel the start of my first orgasm I saw the door opening, and my old body coming in, naked, bringing my girlfriend with him.
"That's my bro! What do you say we bang them together man? I told my girlfriend you too had a big dick and she loved the idea of having a foursome! I bet she's already addicted to the dick huh?"
And while that scene horrified me, the idea of my girlfriend being done by my body and my brother while I was in this one, the humiliation of her seeing me taking dick and not even knowing it was me, it all sent me over the edge and I screamed, cumming "YEEEEESSSS!!!"