followers vs fandom

followers and fandom both are nouns.

Word	Noun	Adjective	Verb	Adverb
followers	Yes	No	No	No
fandom	Yes	No	No	No

As nouns, fandom is a hyponym of followers; that is, fandom is a word with a more specific, narrower meaning than followers:

Other hyponyms of followers include claque, faithful.

followers (noun)	fandom (noun)
a group of followers or enthusiasts	the fans of a sport or famous person