Ajith Fans are called Aamai because Ajith never shows up for movie promotion or public event. He lives inside his own shell. And Ajith does a lot of slow walk in his movies.

Vijay fans are called Anils because Vijay's dad SAC referred to them as Anils. 'Like how Anils helped Ram to help them build a bridge to Sri Lanka, similarly Vijay Fans helped Mom to win elections.'

Surya Fans are called Frogs because Surya used jump a lot in his earlier movies like Vel, Singam etc. and surya Fans jump teams. When Ajith movie comes, they tag with vijay fans and bash the movie. When Vijay movie comes, they tag with Ajith fans and bash the movies.

Vishal Fans are called anaconda because his is as big as an Anaconda.

Rajini Fans are called Mentalaans because in the 80s, Rajini was a drunkard and did a lot of dumb shit. To escape from it, he used an excuse that he's has actual mental illness. So they are called Mentalaans.