It depends on the relationship between the man and the woman.
If it is sexual, it is called a heterosexual relationship.
Pre-marital relationship between man and woman is haraam, absolutley forbidden.
Galileo was a man and his mistress a woman
A relationship between a man and a woman that only has the two people.
close in age
to have a lawful and blessed relationship between a man and a woman
it is to create new life for man and women.
A man is his sister's son's Uncle. A woman is her sister's son's Aunt .
Yes, it's possible.
Man and woman must not cheat in a relationship, and if they do, their relationship would be vulnerable to sexually transmitted diseases, and domestic feuds.
If you are referring to the relationship between a man and a woman it means it is free from physical desire. But then in this corrupt world it also can relate to the same sex relationship.