?

Not sure how to do that? I often get hard while talking to people...

Yep. A couple of times over the years

I jacked off once on an American Airlines flight in the seat next to a woman. She didn't notice.

i came to my sister in law in front of her

When I was a teen I jerked off in the night in a makeshift bed next to my best friend while he slept. I thought about his mother the whole time.

Oh yes i sleept on a school holiday in the same bed with a hot girl i was dry humping on the bed a starred her face while i got closer and closer to orgasm it was so hot to feel her breath on my face and came very hard in my pants thinking she could weak up and see my orgasm face i was humping so close to her my nose was almost touching her nose

I was living in S.London some years ago, and there was a really hot girl working in a local Chinese Take Away. I had to wank to her. So I wore a coat and cut some old jeans up so that I was completely open around my thighs and balls. I knew it would be quiet at the time.
I wanked up a bit before visiting so that I was already edged up. It was a 100 mtrs or so to the Chinese, as I entered it was perfect, no-one in and she was there. It was a high counter and she would be unable to see. I spent a short while choosing my takeaway all the while looking and wanking at her with my coat open, my cock hard and erect. She came to take my order and I was leaning aginst the counter on one arm and wanking my cock with the other.
She took the order, and I was able to still wank to her a she did other things. It didn't take long for my order to be ready and as she brought it to me as she reached the counter I erupted splashing cum all down the front of the counter whilst looking her in the eye as she said thank you.
I pulled my coat together and turned to leave just as someone came in. They must have seen my cum dripping down the counter. I didn't hang around.

In front of? No, but I did rub my cock thru the pocket of my pants in the mall, while following a pair of legs in black tights and heels. She got on the escalator and I got on right behind her. I orgasmed with her hosed legs less than three feet from me. I really tried to hide my moan when cumming. She never turned around.

That was long before the mega security cameras ee have these days.

Years ago I was on an airplane sitting next to a drop-dead gorgeous woman in her 30's, dressed in very a nice business suit. She took off her jacket before sitting down, and her large tits pressed her white blouse out beautifully. Her legs were stunning, especially when she kicked off her heels and I saw her bare feet. She ended up falling asleep, and as she became relaxed, she leaned over and rested her head against my shoulder. Her silky black hair was tickling my face, and she even started snoring a bit. In no way did I want to disturb her, because it was hot that she was in contact with me and didnt realize it. I reached down into my pocket and stroked my hard cock through the fabric. My face was literally just a couple of inches from hers. I was staring at her beautifully made-up eyes, and her beautiful face. I wanted to touch her hair, and I fantasized about kissing her. I could peek down her blouse and see her bra and cleavage. I admired her fit legs, and her super sexy little feet. Then I'd come back and stare at her face and closed eyes, and just took in how beautiful she was. I kept stroking ever-so-slowly so that I would not wake her. If she woke up and opened her eyes, I would be SO BUSTED, but she just kept sleeping. When my orgasm came, I came so hard in my pants for her!!! It was so intense, and hard for me to control my breathing and movements. Later she woke up, and she was embarrassed that she was leaning on me. I told her it was not a problem, and she and I chatted a bit. It was a turn-on to feel my wet cum in my pants as she and I just shared small-talk until the plane landed.

On trains commuting a couple of time when a nice nyloned business woman has been asleep - or at least resting her eyes - nearby.

Then the guilty wet patch on front of work trousers had to be dried off in the toilets under the hand drier.

Wouldn't the intense smell of sperm be noted by those ladies or people around? Sitting besides in an airplane or opposite on a train is super close not to be noticed.

I have numerous times over the years. While in a Airplane, riding on a bus or car and at restaurants, bars and movie theaters. I love to secretly massage my cock when around people until I cum. I've only been caught a few times.

I have a couple of times but I am pretty sure both times they knew what I was doing
Once in school with a teacher with big boobs
Second time was with a neighbour I fancied

On the couch while my cousin was laying on the floor in front of me thinking of her the entire time.