Demons all have at least one item they ALWAYS have on them. The item, which they can choose, will become their callar. It will light up, for demons it will flash red, for angels blue, and it will beep to alert the carrier of their summoning
In the event that the demon answers the call, they will leave a bit of personal fire behind to ensure easy transport back to their original position, and basically teleportation but like idk if it's all demons or just DeVs that operate this way. DeVs can leave a bit of fire so their particles have something to travel to, effectively teleporting them. When they answer a summon, they're just teleporting to a different fire really idk
Obv teleporting is kinda physically taxing so something that can aid in energy efficiency is lit candles, any fire will do but candles smell nice and are easy to control. Consuming the fire will energize them, that's why candles are used in summoning rituals, it makes it easier for demons to make their way to and from the summoner.
So basically a summoner will first have to do the summoning, methods of summoning depend on who/what you're trying to summon, I'll use a general DeV summon as an example.
So the summoner will make the DeV symbol (/deal marker) (material varies, Lucifer uses Paprika, Lucious uses Cinnamon, Cecil uses liquefied eucalyptus leaves, etc, to draw out the symbol) and light a few candles (any amount works really, but the minimum a demon will actually answer to is about 6, any less isn't worth the energy, and frankly, is a little insulting. A better bet is around 12 at least, this will more or less ensure the demon shows up, but more is always better, especially when in multiples of 6). Extra steps are dependant on the specific ritual.
When a demon receives the notification of their summoming via their Callar, they can either deny or accept. If they accept, they will leave a bit of personal flame behind as a way to get back to their original position. They will enter the summoners circle bathed in flame, revealing themselves through the fire and smoke. They'll do their business, and consume the flame from the candles on the way out, teleporting back to their flame and going about with their day.
Something else they can do with that flame; just fuckin leave it anywhere and you can just teleport around. Throw the fire. Teleport over there. Super physically draining, but like, teleportation basically
This works because the particles a demon can turn themselves into are attracted to eachother, and as fire is a part of the demon, the particles are attracted to that flame. The flame can't really move, but the particles can move freely, so the particles move to the flame and not the other way around (the flame is pointed toward the demon at all times, kinda like a compass but instead of pointing north it's pointing at the demon. This is also a way thay parents/guardians can know where their children are at all times, take a bit of their flame, and it acts like a compass, leading you to your child)
