LF4, a Neopets user commonly spotted on the FC (the Fan Clubs, a Neoboard), spiced up the boards by linking a series of userlookups and petpages. Together, LF4 (username: ladyfinger4) and a few other users with strange, numerical usernames, posted all kinds of weird babble on the Neoboards. People rushed to 'decode' it, even interrogating the users at one point. All in all,
the whole thing turned out to be a frickin' hilarious ( and fun) 'hoax'.

Since then, Senders (death threat senders on the boards) have mimicked LF4's techniques (the number-babble the users called "codec" or "code C"). They were...less than successful?

A buzz word being used to refer to creators and influencers forming or encouraging unhealthy relationships with their fans. Usually used in the context of young audiences feeling they have a relationship with the influencer due to the huge amount of the influencer’s content they consume. The influencer in question, however, is unaware of the fan’s existence other than the general knowledge of having fans. Common examples include Dream and his stans. These relationships are exacerbated by the influencers confirming they have more than a creator-to-viewer relationship.

The word is circulating due to various YouTube essays about the phenomenon using the word, and therefore people who enjoy complaining about influencers repeating what they heard in the video in any comments section they can find.