A Lush and Seething Hell is a collection of two novellas: The Sea Dreams It Is the Sky, where vast magical forces play with death and torture in a fictional Chile inspired South-American country, and My Heart Struck Sorrow, a story of dark magic working through verse and song.
John Hornor Jacobs writes well, dragging the reader into the worlds of his mind, however I found it difficult to stay there. Perhaps it's the alert lifestyle of today, full of interruptions and distractions, but it felt easy for me to stop reading and it needed some effort to start again. It took me two weeks to read it all and even then it required a conscious decision to push through, though it's not a large book.
Both stories have a common structure: people who are following the narrative of another and thus are drawn into the same world. Reading about reading, so to speak. They have elements of cosmic horror, although most of it is implied or not clearly explained - the traditional way of approaching the genre - intimating that even the tiniest brushes with these hidden realms are terrifyingly dangerous. What they both reminded me repeatedly is House of Leaves, though not so convolutedly detailed, and only marginally of any Lovecraftian work.
Bottom line: I liked both stories, the world building, the style, the slowly getting under the skin horror elements, but I did feel the writing dragged a little.