If my partner and i were both tested (with a full planet) and clean, is it safe to have unprotected sex? you cant just make a sti/std out of thin air right?

Well, I guess as long as its a “full planet” how can things go wrong??? No, you can’t make an STD out of thin air but what exactly do you mean by “tested”? Sure, you were probably tested for gonorrhea and chlamydia. But how about for Herpes?, for Parvovirus?, for trichomonas?, for syphilis? I don’t think so. Maybe just a little bit of caution is worth it

Yes, if you both are examined, tested and cleared by your doctor(s) and you think your partner is faithful, no need for protected sex and that is not different between a married couple. And yes, if both of you are healthy, you will not get STD.