Medieval society was full of social evils. Some of these were early marriage, slavery system, satee system and so on. In this period, people had very hard and struggled life. Girls were not allowed to exhibit even their face to any unknown persons.
Most of these customs are brought from Hindu and Buddhist traditions. People of diverse religion and belief are the dominant features of Nepali society. Hinduism, Buddhism, Islam and Christianity are the major religions that are practiced in Nepal. People have a sense of unity, though living in the diversity.
Hopefully this helps you out :)