Coming from those artists I know who has patreon its usually a combination of these things:
- An early access of the next chapter -- or it can be a sneak peak
- Bonus Chapters/ Extras
- Sketches/early designs
- NSFW chapters/ Uncensored arts (if they're working on mature content)
-And/or Exclusive artworks of the content they're making
For others (but usually not many have this service):
Aside from those mentioned above, they include at least one merch/items for their fans depending on the tier/pledge like:
- acrylic charms
-prints/postcards
-original sketch
