He earned a living by singing on the street, and sold postcards printed from the photos he took during his journey. Some of these postcards were hung on a wall of the library, on each of which he had written a few lines of prose.

He was on a tight budget, but still volunteered to teach music in a village school in Yunnan for a month.

Before setting off on this trip, he had worked as a technician in an IT company, living a life "that was too stable and changeless for me to want to go on".

"I shared my stories not to encourage others to quit their jobs like I did," Yu said. "I just want to tell them that once outside our comfort zone, we may find the beauty of life that we've never imagined before."

During his trip, he made a friend who later turned out to be the owner of a large company and a millionaire.

"She told me she envied my freedom," Yu said. "It feels exceptional to be envied by a millionaire."

Besides Yu, there were a housewife doing charity work, a campus folk singer, an architect studying Tibetan architecture and a bisexual who shared their stories.

Li Xingning said the "living books" were chosen as they had followed their dreams. Every day at least one human book will be available in the library, she said.

The library also has an online version, where people outside Beijing can share their stories.