Brother-in-law's birthday

A short story but I hope you enjoy it. We went to my brother-in-law's house with my girlfriend to celebrate the birthday of my girlfriend's brother, just the four of us, and we arrived calmly and got ready to go to his balcony. We spent chatting for several minutes, and my brother-in-law asked me if I'd like to accompany him to his room; I said yes, and he told me to come in, but the door was stuck, so I sat down and he said I have a lot of confidence with you, can you do me a favor? I said of course, what's the favor? He looked nervous and said could you suck my cock to see how it feels when a man does it? I left cut off without knowing what to say. After some back-and-forth talking, I accepted. He told me to use my boxer as a thong because you have good butt, and I didn't want to argue so I did it. I took off my pants and used the boxer as a thong; he said wow, your brother-in-law has a great butt and I told him to shut up. I got down on my knees in front of him, pulled out his cock, and started masturbating it gently to make it harder, and he said please start sucking. I did it, starting from the tip, sucking softly until I had taken it all into my mouth; then I started sucking with both hands because his cock was big and hard to swallow. After a while, he stretched out his arm to my boxer and started pulling it several times, making me move my butt and saying your butt is nice, brother-in-law - I just told him to shut up. After sucking for a while, he asked me for another favor, which was to rub his cock against my butt; I was already speechless and said go ahead, take advantage of the situation. He got behind me and started moving like he was screwing me, and I was already red with excitement, telling him not to stop until I felt semen filling up my butt and anus. penis, after that I used his fingers and massaged my anus with his fingers and the semen. After he gave me something to clean up with and we went back to the balcony and this is what happened only my brother-in-law and I know.