When you intensely hook a woman in the vagina with one hand to make her squirt and with the other hand pull her head on your dick to deepthroat her profoundly until she starts puking on your dick, creating the ripple effect of making her vagina contract even more and discharge an even more massive amount of liquid
Your sister was a bit tense yesterday, after a good session of double-sided dutch squirtfest she felt much more releived...