To ensure smooth communications with social media users, Liu set up an account on the popular WeChat instant messaging platform in 2015. A year later the account's followers exceeded 100,000.

There was a period when he was either working in the hospital or writing articles on social media except for several hours of sleep.

"When I realized it was impossible to strike a balance between work, life and popularizing medical knowledge, it was time to give up something."

Unsure of what to do, he turned to a supervisor, a gynecologist with years of clinical experience.

"He said he might meet about 100,000 outpatients over a lifetime. But I was still young, he said, and as long as I kept passing on my knowledge responsibly it was possible that over time I might help up to a million people in some way."

So Liu quit his hospital job and now has 1.9 million followers on Sina Weibo.

However, even today he still receives messages from followers asking whether cervical erosion needs medical treatment.

Liu, who labeled himself as a translator and loudspeaker of medical knowledge, decided to diversify the way he popularizes knowledge, from pure texts to vivid pictures.

"I firmly believe that if one didn't understand what I said, the same information needs to be conveyed in another way."

So he started to use food as props in 2019. The idea came to him when he was buying a bottle of waxberry juice in the supermarket.

"It dawned on me that the juice looks very much like menstrual blood," he said.

"Many girls are worried that they are bleeding too much or too little during their period, even though I tell them it is normal for between 5 to 80 milliliters. But they still don't know what it looks like exactly on the pad."

With the help of waxberry juice, Liu can tell his followers that 1 ml of blood on a pad is about the size of a one yuan coin.

Below the post, a user's comment saying that "This is the most visual knowledge popularization on menstrual blood that I have ever seen "was liked by 129 people.

Later, Liu cast his eyes on watermelon, cantaloupe and even doughnuts, a vivid imitation of the cervix.

As videos became popular on social media, he also started to make ones that responded to gynecological-related issues that many people do not understand, including "Are all gynecological diseases related to sex?" and "How come pregnancy is possible even if condoms are used?"

In July 2019 his manual that aims to help females take care of themselves was published, and more than 400,000 copies have been sold.

Popularizing knowledge is a fraught business, because sometimes people disagree strongly with what you say, often in ways that are often difficult to turn a blind eye to.

"We all have our own ways of dealing with the world, which can include love or in a spirit of criticism or of reflection," Liu said.

"I choose to love the world."

Liu said he will continue to diversify the ways he popularizes knowledge, including setting up a radio program and working with video sharers on Bilibili, a streaming site with up to 200 million active users, most of them young Chinese.

One of three books he plans to publish this year aims to provide instructions on health, gender knowledge and affection, the target audience being girls aged 10 to 18.

"If you look at the various types of social media platforms as planets, I'm only someone with 1.9 million followers on the planet named Sina Weibo and maybe only some of the followers have carefully read all my posts," Liu said.

"When I look around, I find that many more people who are not even on these planets also need the knowledge that I happen to know."