Although the word 'gentleman' in English often has classist connotations, the true meaning of the word is suggested by its very form: a gentleman is man who is gentle. As Mr Banks from Mary Poppins would say
"Gentle but firm, noblesse oblige."A gentleman treats others, including women and children, with gentle care and will never engage in abusive behaviour, i.e. prey on those who are vulnerable or who are under him in the proverbial social ladder.
Many young women seem drawn to men who are not gentle and indeed many young men seem drawn to women who are not caring but this is perhaps for the best in so far as both sexes will eventually come to appreciate gentle, caring partners in the long run after having learnt from the mistakes of their youth.