In a candle-lit room set aside for Satanic ceremonies, a neon sign welcomes you to The Little Black Chapel.
But Christian protesters from many denominations have gathered outside the hotel, carrying signs warning of damnation.
“Repent and believe the Gospel,” urges one.
“Satan rules over all the children of pride,” says another – the letters of “pride” shaded in the rainbow colours of the LGBTQ Pride flag.
“We are hoping to show God that we do not accept this blasphemy, and that we Catholics have not abandoned the public square to Satanists,” says protester Michael Shivler, from a conservative Catholic group.
Convention-goers in the lobby eye the protest outside.
A raised altar stands at one end, a white pentagram on the floor in front of it.
The ritual being performed here is an “unbaptism”, in which participants symbolically reject religious rites performed when they were children.
“No names,” says a Satanist who agreed to let me witness their ceremony, as long as they aren’t identified.
They wear a floor-length, hooded cloak and a black face mask.
Their hands are bound with rope, which is then cast off to represent liberation.
Pages are torn out of a Bible to symbolise overturning their Christian baptism.
It’s clear the experience was powerful for them.
“As a gay child, being told you are an abomination and should be destroyed, warped a lot of my thinking. Finding The Satanic Temple has really helped me embrace logic and empathy.”
The Satanic Temple is recognised as a religion by the US government, and has ministers and congregations in America, Europe and Australia.
More than 830 people snapped up tickets for its late April convention, dubbed SatanCon.
Members say they don’t actually believe in a literal Lucifer or Hell.
Instead, they say Satan is a metaphor for questioning authority, and grounding your beliefs in science. The sense of community around these shared values makes it a religion, they say.
They do use the symbols of Satan for rituals – for example when celebrating a wedding or adopting a new name.
That might include having an upside-down neon cross on your altar while shouting: “Hail Satan!”
For many Christians, this is serious blasphemy.
“That’s not wrong,” agrees Dex Desjardins, a spokesperson for The Satanic Temple. “A lot of our imagery is inherently blasphemous.
The Satanists say they respect everyone’s right to choose their faith, and they’re not trying to upset people.