How big is a risk to get some STD if we practice anal sex without condom

How big is a risk to get some STD if we practice anal sex without condom alternating it with regular sex? (Male, 24 y. o.)

Have to say that there is a big risk of infecting with sexually transmitted diseases (SDT’s) during any unprotected sex. Talking about anal sex, there is an extra risk to get infected not only with STD’s but also with pathogenic microflora. There are plenty of different germs in intestinal canal. If, for example, intestinal bacillus which is normal in intestinal canal gets into uro-genital tract, it can cause inflammation process for man as well as for woman. This inflammation is usually chronic and hard to treat.

Why do men like anal sex? Is that normal if my husband is asking for it?
I have pleasure when I have my clitoris stimulated