Follower is but an Anglicism introduced by the ultra-late use of social networks and by the intellectual laziness of not using our language correctly. Follower is an English word that has exactly the same meaning as a follower in Spanish that, according to the SAR, is an adjective that applies to the one who follows something or someone. Apply people and can be used as a noun. If you find that it sounds very crude, in Spanish we have a more fashionable synonym that perfectly replaces follower; it is the word FAN accepted by the Royal Academy and derived from the English fanatic. So, instead of saying I'm a follower of your youtube channel; you can say I'm a fan or a follower of your youtube channel.