If what you're asking is, he touched his pants and then touched your vulva, do you have a pregnancy risk, it's very unlikely or very low.
If what you're asking is that he touched his pants and then touched your hand and then YOU touched your vulva, it's astronomically low.
Still, if there's any fluid contact going on, for both of your peace of mind it would be best if there were a condom involved.
Does this help?
"And when the answer that you want/Is in the question that you state/Come what may..." - Coheed and Cambria, "Blood Red Summer"