Phusro is a Highgod-level Volcano Titan. He used to be the pet of Elquin, but while he was stronger he could not go against Elquin due to the master-servant bond they had. He has since become a Sovereign's Emissary of the Lesser Fire Sovereign Bluefire.
Phusro has a total of 3 forms:
1) Volcano Titan form. In this form, he is very, very big. He was so big that people called him the Biss Volcano Range, one of the most dangerous areas in the Infernal Realm. His body is that of a volcano-like beast that is likely humanoid as Volcano Titans are more advanced forms of Flame Tyrants. In this form, he can freely control the magma, fires and rocks in his body at will, with devastating results due to his immense power. He can change the trajectory of the rocks that he shoots out at will as well as rearrange the matter in his volcano-like body to form tunnels and walls, so he can trap other people in it. He also can control golden magma known as Liquefied Goldflame that is deadly to Deities, but can choose who can be affected by it (it only kills those that he wants to kill).
2) Kitten form. In this form, he appears as an adorable small golden kitten and he can mew like an actual cat. He is capable of maintaining both his Volcano Titan form and kitten form at the same time. He was forced to assume this form due to Elquin's fondness for cats, but in truth, he hates this form. Utterly.
3) Humanoid/human form. In this form, Phusro is 3 meters tall and wears fiery red armour. He has scarlet hair and a craggy form, and is very muscular.
He was the magical beast of the Seven-star Fiend Elquin for trillions of years, having been captured as a Saint. While he was stronger than Elquin, the master-servant bond they had stopped him from acting against him.
He kills the 2 Highgods accompanying Inigo with flying pebbles from his Volcano Titan body easily.
In subsequent chapters, he launches an attack on the metallic lifeform containing Linley and the other fiends with fiery boulders under orders from Elquin, killing Bachelor as well as many other Fiends He then traps all the surviving Fiends along with their client within his Volcano Titan body. He rearranges the tunnels to direct Linley's group to the Goldflame Pool while keeping the more powerful Fiends trapped in a different location. He then attacks the group with the Liquiefied Goldflame, killing several of them.
After Elquin appears and Salomon bargains for Linley's death, he drags Linley, Delia, Bebe and all the other Deities into the Goldflame Pool, but he spares Linley, Delia and Bebe as Elquin does not want to incur the wrath of Beirut. He stops them from leaving the pool until Salomon and Nisse leave. Phusro then directs Learmonth to the Goldflame Pool, allowing him to kill both Inigo and Elquin.
After Elquin's death, he transforms into his human form and attacks Learmonth and rants to Linley, Delia and Bebe as a form of venting the anger, grief and depression he built up over trillions of years. He reveals he has fused 5 of the 6 Profound Mysteries in the Laws of Fire and his utter hatred of kittens. It is likely he will never assume his kitten form again. After venting, he gives them over 100 interspatial rings as a form of gratitude for listening to him complain, then leaves saying he will roam the Infernal Realm. The Biss Volcano Range thus disappears.
The next time he makes a reappearance he interferes with the fight between Linley and Elder Bulo. He threatens Bulo against harming Linley, and chats with Linley before leaving.
- He was first introduced in Book 15 chapter 14, as the pet of Elquin. He kills the 2 Highgods accompanying Inigo with flying pebbles from his Volcano Titan body easily.
- Sometime in the past, he disguised himself as the Biss Volcano Range and killed many Deities, accumulating all their wealth and treasures under Elquin's orders. He has also fused 5 of 6 Profound Mysteries in the Laws of Fire.
- He later makes a reappearance in Book 17 chapter 41, telling Bebe about Carolina's message. When Linley is attacked after leaving Meer City, he kills an enemy Elder. After the battle, he reveals the nature of the attack that Delia suffered and accompanies Linley back to the Skyrite Mountains. Back at the Skyrite Mountains, he engages in a secret discussion with the Patriarch.