Is it unsanitary to kiss a rat on its nose or mouth?

i hav male rat who is health, clean and so cute! i like to give him kissed on his mouth and nose because i love him so much lol... and he kissed me on the mouth and all over too! i was wondering is it bad or unsanitary to do this? lol because my moms Always like don't kiss it on the mouth that's gross// but i do it anyway :)