Personality
Despite his shock humor and turbulent lifestyle, Putnam was often described by fans and peers as a warm, intelligent, and sensitive person. Putnam saw himself as a comedian and used music as an outlet. Following his death in 2011, The Guardian dubbed Putnam "the GG Allin of grindcore".
In school, classmates who knew Putnam described him as intelligent and stern, but unmotivated, apathetic and often an underwhelming student. Putnam skipped a grade in school and became a very bright student, tutoring his classmates. In his own words, Putnam often blamed brutal fights with Catholic school nuns for helping to shape his cynical personality. When he reached high school, he had lost interest in excelling in education or academics, becoming more of a slacker and underachiever. By the time he had graduated school, Putnam had left the Catholic religion in which he was raised. After graduating from Newton North High School in 1985, Putnam showed no interest in attending college or university.
Putnam also made up his own religion when he was a child. He stated his all-time favorite bands were Negative Approach and The Village People, and that his favorite movie was The Bad Bunch. He also stated that he didn’t pay attention to any music that was made after 1985.
The 2018 grindcore documentary Slave to the Grind explores Putnam in detail, with his peers expressing the duality of his nature: former bandmates Tim Morse and Scott Hull describe Putnam often being personable and relaxed, but Hull also notes that he'd often get arrested causing trouble on the street. Discordance Axis singer Jon Chang notes that he was really close to Putnam for years, but describes him as a "really disturbed guy" and a "backstabbing piece of shit at the end of his life". Chang also recounted an incident after a show when Putnam introduced his mother to Chang, he remarked that they had met earlier when he pulled Putnam's mother out from the show's moshpit, causing Putnam to become aggressive and threaten Chang, much to the confusion of everyone present.
Putnam was also good friends with Pantera frontman Philip Anselmo. Anselmo used to get Anal Cunt to open for Pantera whenever they went through Boston. Anal Cunt opened for Pantera three times. Putnam recorded backing vocals for Pantera's album The Great Southern Trendkill. Putnam also released a medley of the Pantera songs The Great Southern Trendkill and Rock the World for the Anal Cunt album The Old Stuff Part 3. Putnam referenced Pantera in the song Loudest Stereo. There is also footage of Putnam singing "Suicide Note Part II" with Anselmo at a show in 1998.
In 2019, Brutal Truth and Venomous Concept vocalist Kevin Sharp did an interview with Metal Underground and talked about a conversation he had with Seth after his coma. He also said that Putnam was an "encyclopedia of music".
According to Eyehategod vocalist Mike Williams, Putnam was a normal guy off-stage and very quiet and soft-spoken. Williams also stated that he used to call Putnam, whom he had known since 1988, long distance from the Chevron gas station that he worked at, so that all his calls would be charged to Chevron.