That's semen,its normal dear
it will *only allow* not "allows."
Presumably the sperm is getting out of your vagina, but what you're probably seeing come out of your vagina is semen. Sperm is microscopic, and is inside the semen, which is the thick, clearish liquid.
Of course it comes out of your vagina -- a vagina is a sheath, not an opening into the inside of your stomach or anything. It ends where the uterus is. There is a small opening at the end of the uterus, but it does not accommodate all that thick semen, it will allows the little sperms in. Think of it as passengers getting off a 747 -- the airplane does not enter the terminal, only the passengers, and the airplane then backs out of the parking area. Semen drops off its spermie passengers and then drains naturally out of the vagina when you stand up or otherwise shift your position.