You have to know which parts of the penis to stimulate. Read about the frenulum of the penis. Number 5 in this link:
link
Sit on him (do cowgirl) and raise up on him until you can feel the end of his penis with your vaginal walls. Also feel, with your vagina the ridge area of his penis. This will be close enough to rub his frenulum with your vaginal walls. The shaft does nothing for us towards having an orgasm so just concentrate rubbing the walls of your vagaina on the upper part of his penis particularly the ridge, if you can feel it. Just keep working this area slowly at first watching his reaction. As it appears his breathing is becoming more rapid start going faster on this area. No guy will be able to hold on to his sperm for long if you keep working that specific area. The only limitation will be how long your legs can hold out until he pops.
It's the same if you're giving him a hand or blow job. Forget about the shaft. Just concentrate on stimulating his frenulum. You'll have sperm eruping in the air in no time or a mouthful of sperm very quick.
Have fun.
If you're just using your hands or oral some guys can't come from that.
Let him keep going during intercourse until cums, use lube if it starts to hurt. He should be able to come from the feeling of your vagina.
Maybe he has a problem? If he can come by himself but not with you it might be a psychological problem, trust issues or something like that.
Or it could be the same problem as with my boyfriend. He had gotten used to the feeling of his hand and it took a few months for him to get used to the feeling of me instead and let the sensitivity come back.
We're all good now though so talk to him and tell him what you wrote here. Even if he doesn't mind, you do.
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