The manuscripts are on paper. It eats trees, so that's easy enough to do. I don't know what the ink is, but probably not blood. The balloons aren't necessarily hide, they might just be membranes or something. You're walking along, and GIANT FLOATING STOMACH! with a play attached by DISGUSTING TENDON! that's basically the next Shakespeare.
I'm leery of giving a sample of the normal text, mostly because I don't have the confidence in my writing ability. It'd be pretty annoying if an article explicitly states that a work is high quality and what I present doesn't meet the reader's expectations. But I can do crazy rant pretty well. An early draft of that. Sufficiently insane? And does it convey that maybe humans aren't the "Great Ones", but we're pretty lucky it thinks that?
Excerpt from one of SCP-XXX's "bad" manuscripts, capitalization, emphasis and grammar preserved, color omitted:
Cleanse the WORLD for the Great Ones Cleanse the WORLD for the Great Ones
who greater than you your majesty your sublime nature Great Ones do I do right?
The flesh and wood serve you unite with the steel you love do you love me too I am what you love. Great Ones see as I do my duty my passion
forgive the slowpace the steel takes TIME. Did you like the servants they were the BEST of the cleansed only the BEST for you Great Ones made like you form you assume here on a WORLD to clean to honor you do appreciate please please I will complete the cleansing soon and you can take me away in your ships of FIRE and I can love you and you will love me