Thanks for your care and concern. As you may know, genital herpes can be spread through genital penetrative sex, oral sex or anal sex from an affected person to the un-affected. Presence of visual evidence is not necessary for genital herpes to be seen. Only clinical diagnosis of presence of antibody in blood can reveal whether a person is infected or not. So, it is important to get some medical tests done to ensure that you are free from infection. You may consult your doctor to get tests like viral culture, direct fluorescence antibody, type specific serum tests and poly merase chain reaction tests done. These tests can be used to get it confirmed about the presence of virus and infection. Anyway, if his herpes is due to type2 HSV, you are unlikely to get affected through the method you have mentioned in the question, while having sex. Hope my answer helps. Best wishes.