How likely is it to be pregnant if the guy cums 5 times in 3 days 3-4 days after the period?

Possible: It is possible to conceive at any time during the cycle, before or after the period. Use protection if you do not wish to be pregnant. See your healthcare provider.

More likely than if: Unprotected sex after menses is more likely to lead to pregnancy than if immediately before menses. Sperm can live a few days inside your body. Ovulation occurs 2wks prior to menses. So sex a few days before ovulation can still result in pregnancy but less likely 7-10d prior. If you're worried, wait until 4wks past last menstrual period & take home pregnancy test. Use birth control if don't want.