Molly started her life as a stowaway cabin boy, running away from an arranged marriage and only just missed being thrown overboard when she was found out, but was dumped off on land instead.
She became a pirate by accident.
If we are talking historically, no-one who sailed was 'very nice', it was bloody hard being a member of any crew.
However, the crews of pirate ships were usually very close knit and very loyal to each other once they got their pecking order sorted. As with any other ship, some were ruled by tyrany, some by fareness.