Lunar Park by Bret Easton Ellis

A metafictional horror novel in which novelist Bret Easton Ellis,
married to actress Jayne Dennis, relapses into drugs while teaching at
a college, haunts his suburban home with visions tied to American
Psycho, and confronts supernatural violence as missing boys and
copycat murders multiply.  

This book contains; abortion, activism (referenced), alcohol
(excessive), alternate gender or sexual ideologies, animal
cruelty/neglect, anxiety (pervasive), BDSM (elements), bestiality
(disturbing reference), body horror, body shaming, bullying,
cannibalism (referenced), child abuse, controversial cultural, gender,
historical, political, racial, religious and social commentary, dark
content (supernatural/paranormal), death/grief, deception, demonic
content (elements), depression, derogatory terms, drugs (excessive), dubious consent, erotica, explicit sexual activities/nudity, explicit sexual dialogue, fetishes (referenced), gore, horror, kinks, misogyny, molestation, murder, non-sexual nudity, parental neglect, patently offensive sexual content, pedophilia, pervasively vulgar content, porn, profanity, prostitution (referenced), prurient behaviors, psychological distress, rape/sexual assault, self-destructive behavior, sex exploitation, sex toys, sexism, sexual nudity, smoking, stalking, suicide (referenced), theft, torture, toxic relationships, violence, and voyeurism (elements).