Chen Jianxing works for Tanzania National Parks. The job enables him to watch lions freely. Photos provided by Chen Jianxing

"When I was a boy, I made a wish that one day I would go to Tanzania and see real lions," says Chen.

At 15, Chen spent half a year writing a book about an imaginary lion living at the Serengeti in northern Tanzania. It was a draft. But in 2013, his first book recording the life of the Manze pride was published in China, containing many photos he had taken.

"In the 1990s, most Chinese had no idea about Africa. But I watched so much of it and collected as many materials as I could, so I felt it was like my second hometown," Chen says.

In 2010, Chen started his new job working for the Tanzania National Parks' new project in the Selous Game Reserve, one of the largest mammal reserves in the world and home to about 4,000 lions.

Chen's workplace is a 40-minute drive to Lake Manze in the Selous, where he first met the Manze pride of 14 lions. It took about two months for him to make the pride feel comfortable with his presence, and he gave each member a name.

Lisa was then a 10-year-old mother of two lion cubs. The average lifespan for a lioness is about 12 to 15 years. Lisa often roars and shows her sharp teeth to strangers, says Chen, warning them not to be close. But Chen was allowed to stay five to 10 meters away and sometimes even closer.

Generally, tourists on safari would bring bodyguards with them. Chen often sleeps alone in his camp, with lions walking by outside, roaring.