What does pr mean in the barrage?

It means peropero pero (romaji in Japanese), which is an onomatopoeic word for the sound of licking saliva in Chinese. It means that a character is so cute that his mouth is watering. Originated from Japanese video sharing website (niconico animation), it was first introduced to China in the form of AcFun (imitating niconico content) and later in the form of Bili Bili and Tucao.

Extended information ① barrage (dànmù), a Chinese vocabulary, originally meant to provide intensive shelling with a large number or a small number of artillery pieces. Nowadays, it is often used to spit out comments in real time when watching movies, which is reflected in the effect that it looks like a flight shooting game when it floats across the screen.

②PR, the full name of PageRank, was granted an American patent in September of 200 1 year. The patentee is Larry Page, one of the founders of Google.