In Aztec Mythology, Xolotl is the God of Lightning and Fire as well as the God of Monstrosities, Death, Misfortune, Sickness and Deformities
First Evidence : Appearance
Xototl is depicted as a dog headed man with his tongue hanging out from its mouth.
Loki also tends to leave his tongue hanging out like a dog.
Speaking of dog, did you notice there are claw marks inside the Aurust Castle which probably from the result of the battle between King Harold and Loki. Those claw marks looks like it could done by either a feline or a canine-like creature like a dog.
There's also a story that Xolotl lost his eyes because he didn't partake in a ceremony and wept until his eyes fell out of his head. Now Loki although not cofirmed yet maybe also lost his eyes too as it is being covered by bandages.
Second Evidence : Connection to fire and lightning
As I say above, Xolotl is the god of fire and lightning in Aztec mythology. Interestingly in the latest chapter 1141, Ripley mentioned that the only weakness of Elbaf is fire and lightning.
Third Evidence: Connection to monsters, misfortune and death
Aside from being the god of fire and lightning, Xolotl is also the god of monsters, death, misfortune, sickness and deformities which really fits Loki's character. Before Loki was even born, he was already prophesized to bring many misfortune in Elbaf. He was prophesized to kill his father, King Harold. He was also being blamed for the death of the the royal steed, "the horse of fortune", the death of queen and many more tragedies in Elbaf. He is also considered a monster as he killed many ferocious beasts and tamed the rest in the realm of the dead.
Fourth Evidence: Connection to sun
In Aztec mythology Xolotl has a twin brother Quetzalcotl and both of them has connection to the sun. Quetzalcotl acts as the harbinger of the sun the sun's rising every dawn. Xolotl acts as the harbinger of the sun's setting every dusk.
Now although not twins Loki and his brother Hajrudin also has connection to the sun as they both want to be the sun god.
Fifth Evidence: Connection to the underworld
In Aztec mythology there is a place called Mictlan , the land of the dead or underworld. According to the mythology, Xolotl accompanied Quetzacotl to Mictlan to retrieve the bones from the those who inhabited from the previous world.
In Elbaf there is also a Realm of the Dead which is where Loki is imprisoned. Loki mentioned to Luffy that the Realm of the Dead contains countless bones of humans and giants from the "First World". Interestingly he also mentioned that the realm of the dead belongs to the sun.
Conclusion: Loki and his possible devil fruit ability is inspired by Xolotl, The Aztec God of Fire, Lightning, Misfortune, Monsters, Death, Sickness and Deformities.
First Evidence : Appearance
Xototl is depicted as a dog headed man with his tongue hanging out from its mouth.
Loki also tends to leave his tongue hanging out like a dog.

Speaking of dog, did you notice there are claw marks inside the Aurust Castle which probably from the result of the battle between King Harold and Loki. Those claw marks looks like it could done by either a feline or a canine-like creature like a dog.

There's also a story that Xolotl lost his eyes because he didn't partake in a ceremony and wept until his eyes fell out of his head. Now Loki although not cofirmed yet maybe also lost his eyes too as it is being covered by bandages.

Second Evidence : Connection to fire and lightning
As I say above, Xolotl is the god of fire and lightning in Aztec mythology. Interestingly in the latest chapter 1141, Ripley mentioned that the only weakness of Elbaf is fire and lightning.

Third Evidence: Connection to monsters, misfortune and death
Aside from being the god of fire and lightning, Xolotl is also the god of monsters, death, misfortune, sickness and deformities which really fits Loki's character. Before Loki was even born, he was already prophesized to bring many misfortune in Elbaf. He was prophesized to kill his father, King Harold. He was also being blamed for the death of the the royal steed, "the horse of fortune", the death of queen and many more tragedies in Elbaf. He is also considered a monster as he killed many ferocious beasts and tamed the rest in the realm of the dead.


Fourth Evidence: Connection to sun
In Aztec mythology Xolotl has a twin brother Quetzalcotl and both of them has connection to the sun. Quetzalcotl acts as the harbinger of the sun the sun's rising every dawn. Xolotl acts as the harbinger of the sun's setting every dusk.

Now although not twins Loki and his brother Hajrudin also has connection to the sun as they both want to be the sun god.
Fifth Evidence: Connection to the underworld
In Aztec mythology there is a place called Mictlan , the land of the dead or underworld. According to the mythology, Xolotl accompanied Quetzacotl to Mictlan to retrieve the bones from the those who inhabited from the previous world.

In Elbaf there is also a Realm of the Dead which is where Loki is imprisoned. Loki mentioned to Luffy that the Realm of the Dead contains countless bones of humans and giants from the "First World". Interestingly he also mentioned that the realm of the dead belongs to the sun.

Conclusion: Loki and his possible devil fruit ability is inspired by Xolotl, The Aztec God of Fire, Lightning, Misfortune, Monsters, Death, Sickness and Deformities.