Buma and Susu are both upvoters who do video clips about a particular movie, and the two often interact in the comments section together, so you could say they're good friends in the upvoters. Buma and Susu have one thing in common, which is that they are both upfollowed by fans on B. They are both up. referring to the person who uploads a video, the term is often used by the Beep video site, and the uploader of the videos we see on B is the uploader.
Historical background of B station's Buma and Susu's occupation:
UP owner a person who uploads video and audio files on video websites, forums, and ftp sites. An internet term imported from Japan that is frequently used on domestic ACGN video networks.
UP master is a web term imported from Japan and is frequently used in domestic acfun and bilibili video networks. A person who uploads video, audio, and other files to video sites, forums, and ftp sites.
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