Nearly two months have passed since Seth Herter thought he was the Antichrist.

The realization that he was not — made possible through a combination of anti-psychotic and mood-stabilizing medications — came to him in the St. Louis City Justice Center, where he has been locked up since May after slaughtering another man with a samurai sword.

For years, he had talked of himself in online posts as the "White Rider," a reference to the Four Horsemen of the Apocalypse in the Bible's Book of Revelation. He believed he could control all the electricity in the world and that thousands of people were clamoring to see him dance. His delusions had led to a smattering of scrapes and arrests. But in April, his thoughts turned significantly darker.

"I started to feel like it was time to start punishing people," he recalls.

Herter is 29 years old, stands six feet four inches tall and wears a scruffy goatee. In the pale light of a jailhouse visiting booth, a splash of acne reddens his cheeks. He has begun to regain a bit of the weight he lost while fasting during his delusions. He lowers the waistband of his yellow uniform to reveal angry pink patches on both hips — friction burns from a rope he wore cinched around himself for a month, he says. The fasting and the rope were part of a biblically themed penance that Herter believed would increase his powers.

"I got a hairshirt and everything," he says, later adding, "I believed so many crazy things." Convinced the CIA had embedded a chip in his ear, Herter even sat down one day with a mirror and a knife and tried to cut it out. He later went to an urgent care, hoping doctors would find the chip with an X-ray.

He sounds disgusted or embarrassed as he tells these stories, like a person realizing after the fact he has been fooled by an obvious scammer. But in this case, he was tricked by his own mind.

In some ways, it is a relief to return to reality. In others, it is crushing. He knew the man he killed. More than knew — he says they had dated for years. They had recently split up, but Herter says he called his victim on the day of the killing because he thought people were in his walls and furniture, and he needed help clearing them out. His face slowly turns red as he talks, and then he sobs. "I loved him so much," he cries out. "Can you please say that? Please tell people that I'm not a monster."

St. Louis police and a medical examiner's spokeswoman identified the man as 55-year-old Christopher McCarthy. In a probable-cause statement, a detective says McCarthy was stabbed to death. Herter will not discuss "the particulars" of the killing, but he blames his own mental illness.

"It wasn't like I wanted this to happen," he says. "I was in the middle of a psychotic break, and it ended up really bad."

In the anguish of clarity, he says it is a nightmare to learn that so many perceptions he had were wrong and that they cost someone his life. But as the real world and its consequences barrel in, there is one big piece of the puzzle that he can't attribute to delusion or a trick of the mind.

He says he had known the victim for four or five years — a claim supported by others, including a former neighbor — but that the name Christopher McCarthy was new to him.

"I thought his name was Tim," Herter says. "He told me he was Timothy Wilson. When they told me he was Christopher, I was blown away."

Warning: The following page contains a graphic photo of the bloody crime scene. Sensitive readers should proceed with caution.