It shows that a man is very fond of a woman.
Handshaking is a very private act. If a man takes the initiative to shake a woman's hand, it shows that he is very fond of the woman. Perhaps this behavior is unconscious and subconscious. Subconsciously he enjoys intimate contact with women. This is also a kind of temptation. If the woman does not refuse, it shows that she strongly approves of the man's behavior. If a woman objects very fiercely. Then it means that it has no other meaning for men.
Handshaking is a kind of etiquette that originated in Europe in the Middle Ages. The order is senior and young, with ladies first.