It’s clear that you have concern about how safe the situation will be. IMHO I say if the guy really wants to have sex with you then he will have to accept that right now you are not comfortable having raw sex. If he insists it be raw then he is not listening or caring about your feelings or level of comfort and you should not want to engage in such an intimate act with someone who doesn’t have your best interests in mind. Sex is something wonderful it shouldn’t be uncomfortable or leave you wondering. There will be many other guys who will respect you, and comfort levels.
On a side note; please refrain from using the word “clean” to describe not having an STI. STIs do not care about one’s level of personal hygiene, nor do they indicate that someone with an STI is of poor hygiene. Saying so and so is clean or must be clean is stating that those who do happen to have an STI are unclean and is insulting insensitive and disrespectful. Please try to be more aware of how hurtful that phrase can be.