Women are most fertile three days before and during their period. We have eggs inside us that descend from the fallopian tubes and into the uterus. Once in the uterus they find a little home and wait for sperm to fertilize. Whie there the uterus builds up a layer of proteins that help to feed a baby and there is a hormone surge in the woman which causes increased sexual feelings. (also moodiness) The eggs will sit in her uterus for a few days ready to be inseminated and when they are not, her body will flush them out, this is why stuff comes out during period. It is not safe to have unprotected sex during this time because the eggs are not washed out first and are still inside there totally ready to make a person.
She will want to have sex with you because her body is ready to reproduce. You will want to have sex with her because on another level your body picks up on these hormones and instincts of hers and because you are both wanting to have a baby you have unprotected sex.
I'm seriously floored by your lack of knowlege, how can you work the equipment if you never read a manual?
Learn how we work, and for gods sake tell us you bought some condoms.
Be a man and not another punk who's just happy to be getting some and doesn't look out for his girl or his self.