Enseñándole matemáticas a mi yerna.

Hello to all my name is Gustavo I'm 41 years old, I'm 1.84 meters tall, I'm dark-haired, a bit chubby, I'm a math teacher, I'm married, my wife is 39 years old, she works in an accounting office, I have a 19-year-old son who's in university studying civil engineering, he's in his first semesters, the thing is that he has been with a girlfriend of 18 years old for a year now, she studies architecture, she's the most beautiful girl I've ever seen, she's a preciousness, super sexy, has impressive tits

I don't know how my son managed to conquer her, but what a beautiful girl she is, and it seems like she's a devil the way she always dresses in shorts, short skirts, leggings, shirts, and blouses with large cutouts, and in bed it seems like she loves it, judging by what I've heard when they're in my son's room. I told them they could do it in their room, but to use a condom and if her mother finds out, I never knew anything haha I have a very good relationship with my son, we get along very well. One day my son told me that he wanted me to give some classes to his girlfriend Mariale because she was having trouble with some exercises and didn't want to fail, so I said yes, come whenever you want since I'm on vacation and I explained it to him. So Mariale came a Monday at 2 pm, my son was in university and my wife was working, it seemed a bit strange that she would come at that hour and not later, since she lives nearby but I didn't give it much importance. That day she arrived wearing a skirt and a top with super cutout shoulders, her enormous breasts were visible, we sat down in the living room and I started explaining, sometimes I'd throw a glance at those breasties when I finally understood I put some exercises on her and got up to get water, served myself and walked back to the living room while taking a drink and realized that Mariale's skirt had gotten caught on a decoration of the chair so when she sat down that part didn't go down and I could see the beautiful black thread she was wearing, I was amazed then I approached her and said Hey Mariale take down your skirt it got stuck and you can see the whole thread
Mariale: oh what shame grandfather that's a pain excuse me
Me: calm don't bother me at all haha
Mariale: ay grandfather is old
Me: haha I just say you don't have to be sad it's things that happen
Mariale: thanks little father-in-law
Later I saw how they were doing their exercises some good others not, kept explaining until my son arrived, then we left for the next class, she came the next day but came at 10 exactly when my son had left 30 minutes ago to go to university, strange but didn't give it importance again, that day I was wearing a football t-shirt and a football short, she wore a mini short and a cut-out blouse, never saw that mini short almost showed the beginning of her butt so I saidI: Mariale and that short is new?
Mariale: yes I bought it a few days ago but I hadn't put it on, how does it fit?
I: great, but your son lets you leave like that?
Mariale: yes why?
I: I mean, if I were him I wouldn't let you leave the room just because you put that on and then you'd start getting angry haha
Mariale: grandpa!!!!!
I: yeah!!!
Mariale: he can't say those things and especially not to his daughter-in-law
I: but why? I mean what I would do more than what I'm doing haha
Mariale: God, this father-in-law of yours brings up some things hahaHow I saw that she didn't get annoyed is more she started laughing playfully, I went on daring to more, throwing more glances without concealing, until I dared to do this, she was solving some exercises, I went to the bathroom and took off my boxer briefs, I touched myself a bit to leave it half awake, and then I went for water, and approached Mariale to see her exercises, and when I was like that, I pressed my semi-erect penis against her shoulder, but very quickly and said sorry and kept explaining that I was wrong, she didn't say anything so I kept doing it about two more times, let her finish her exercises and since I was very excited I had a quick masturbation, came and got dressed, my son arrived soon after and we left the class for the next day, she arrived with a skirt and a low-cut blouse as always, beautiful in every way, I went on explaining some topics, then left her some exercises and told her I'd go shower, took a shower, touched myself a bit and left it semi-erect and put on a towel, and came out to see how Mariale was doing, reviewed while seeing her throw a glance at my package, found it funny and just as that happened my phone rang which was on the table, I grabbed it and had some WhatsApp messages, while responding without Mariale noticing I relaxed the towel and it fell to the floor leaving my semi-erect cock visible to Mariale who was right next to it, my cock is quite thick and long, measures 19 cm in length and 4.5 cm in width, I acted stupidly and kept looking at my phone writing a message, Mariale wasn't stopping staring at my cock unable to believe it, probably never saw anything like that, until she reacted and said Marial: oh grandfather
I: yes tell me? Have you finished?
To turn around I did it on purpose and stuck my cock in Marial's face

I: oh forgive me Marial I didn't know my towel had fallen off
Marial: oh grandfather it hurt me
I: forgive me jajaja
Marial: that thing is very big almost killed me
I: don't be exaggerated even if it were erect it would kill you jajaja
Marial: comoooo it's not erect yet?
I: no way, it's still sleeping
Marial: poor grandmother
I: jajajaja I'm used to it, my son doesn't treat her like that?
Marial: noooo not even close jajaja
I: what a shame jajaja (she couldn't stop looking at my cock since I hadn't put on the towel yet) I'd show you how it's erect but to keep it completely erect I always need a blow job, I mean, she doesn't stop looking at me jajajaja
Marial: oh forgive me grandfather this is good if you...Saying this, I heard the voice of my son outside the house, so I went to get dressed quickly, we left class for next time, so it passed a couple of days, my son was in classes and my wife at work, the bell rang around 9 am, quite early considering the hours that came, when I opened the door I was amazed she was wearing a mini skirt that if she bent down you could see everything and a white top that only covered those beautiful tits and wasn't using a bra, God got half erect all of a sudden and I was wearing a football short, I made her pass through, I was eating her up with my eyes, already in the dining room we continued where we had left off in the exercises, I saw everything was perfect, I explained another topic and when she understood I gave her some exercises, I went to the bathroom, took off my boxer briefs and was free as they say here, having that short with that thin fabric you could perfectly see my semi-erect cock, I went to the dining room and what a surprise Mariale was resolving the exercises in the dining room but instead of sitting she was standing leaning against the table leaving her whole ass visible, God what a view, she wore a precious red thread super inserted into those buttocks, I approached her from behind sticking my erect and hard cock to her.Without saying more Mariale turned around and got down on her knees, I pulled out my cock and she opened her mouth and uff her tongue passing through the head of my cock was spectacular, she started to put as much in her mouth as she could, sucking my balls, looking at me and I at her, she took out her enormous tits and started doing a Russian on me, God almost came because she was licking the tip of my cock, I grabbed her hair, put her in L position in the living room, opened her ass, did it again on her string, and slowly inserted my cock while she moaned, already with everything inside, I started to push and pull while holding onto her waist and increasing the speed, then I sat down on the chair, mounted her on me, and we started kissing while she rode me, later she sucked my tits, and I told her that now she was mine, my slut, that I would get her pregnant, and she like a madwoman said yes to everything, saying that she was mine, that she belonged to me, that I could do whatever I wanted with her but never leave her alone, hahaha. After an hour, I got her down on her knees again and finished in her throat, she took it all, I cleaned her up and she went to clean and tidy herself, and that's how everything started, I had sex with her whenever I could, did whatever I wanted with her, my son and daughter-in-law never found out, my son proposed to her two years ago and they got married happily, then I fulfilled my promise and got her pregnant, she said she takes care of herself with condoms when she's with him, first they had a girl and later I got her pregnant again and they had a boy, my son has brothers he doesn't know, hahaha.