The Santelmos are sentient entities that can be summoned willingly. They are said have appeared as bouncing balls of fire in the past, but they are shown to commonly appear as a human head. As fire elementals, they can defend themselves through flames and can start raging fires when they lose control. Their affinity to fire also allows them to determine the type of fire used to burn, immolate or commit arson. Their lifespan is considerably long, given that hundred year old Santelmos tend to be childish.
Some Santelmos have been known to be fueled through intense emotion, heightening the longevity and area of effect of their fire. Interestingly, this also draws parallels to eldritch fire, which can also be fueled by intense emotion when put inside a human host.
Santelmo are said to have appeared to humans in province crossroads or floating above the sea. These have been rumored to be the souls of the men who lie at the spots where they manifest, but Alexander Trese notes that the Santelmo they have interacted with are true fire elementals.
In the 1950's, a broken-hearted Santelmo started a fire for three days and three nights in Binondo that would come to be known as the Great Binondo Fire. Alexander Trese helped in stopping the incident, indebting the Santelmo to his family. They are able to be summoned by the family when needed in order to assist them in their various pursuits.
- The Santelmo who started the Great Binondo Fire. He can be summoned by Alexandra through dialing the date of the fire on her phone.
- Liab, a Santelmo said to light up the sky with fireworks.
- A group of three Santelmo that Alexandra can simultaneously summon through her phone.
- Santy, a young Santelmo that knows a lot of recently manifested fire elementals.
- The cellphone as a summoning device was inspired by one of Tony Perez's books.
- Budjette Tan referenced the Great Binondo Fire from a book set titled Filipino Heritage.
- Budjette Tan has said that Santelmo can be summoned alternatively by writing the number of the Great Binondo fire and burning it using a candle lit in front of a mirror. He also said that other people outside the Trese family can summon Santelmo, but are easily provoked if they don't trust them.
- Trese: Book of Murders
- Trese: Book of Murders
- An Act of War
- The Tragic Case of Dr. Burgos
- Trese Lite: Postcard Book 1
- The Fort Bonifacio Massacre
- A comment from https://tresekomix.blogspot.com/2006/04/trese-4-complete-story.html?m=1