It’s incredible how beautiful - and dangerous - fire can be.
Rin is an exceptional example of this.
The blue, vibrant flames he inherited, a symbol of Satan’s power, are not uncontrolled; Despite the belief that fire causes only destruction, his flames are powerful, yet gentle. When Kurikara is drawn, the flames dance across his skin - tightly compacted around his head to form two horns, flickering around his limbs and around his tail - ready to be used to defend those he cares about at his command.
They pulse to the beating of his heart, a steady rhythm that can quickly change into a symphony if he is aggravated. Although the flames bend to his will, they also bend to emotional turmoil - something Rin is very susceptible to. The second his friends are in danger, his flames will ferociously curl around his companions with only three things in mind - protect, defend, shield.
But perhaps even more intriguing: When resting, Rin shows an entirely new side of his fiery powers. Fires die without constantly being fueled; This also applies to fire-based demons. After intense or drawn out battles, these demons must recharge and refuel their flames. They do this by sleeping - a lot.
And Rin sure loves to sleep. It’s not that he’s incredibly lazy (at least, not entirely.) He simply has a natural need to nurture his flames back to useable condition. When touched in his sleep, even slightly, little bubbles of fire the size of a lighter’s flame reach out to lap at the source of the touch. Usually, it’s to suck in any outside source of fuel and make it useful to the sleeping demon. However, Rin’s flames contain their master’s restraint - the fire, according to Shiemi, feels more curious than ravenously hungry.
“It tickles,” she had once said. “Kind of like a cat’s nose brushing against your hand. It’s really cute!”
So, naturally, Rin’s incredible mastery of his flames keep him from absorbing his friends’ souls. What they will absorb, amusingly, is regular food. Bon thinks that the flames literally contain Rin’s love of food; So, when something tasty is set on his body, the flames instantly grapple at it and swallow every last nutrient. Afterwards, as if the flames have minds of their own, the fire will wrap itself around the giver of the food and gently wreathe around them, similar to a cat meowing for more grub.
Rin’s friends quickly learned that a well fed fire demon was a very happy fire demon…and an adorable one. Because once Rin’s body has successfully gobbled up every bit of food it can muster, it directs all that energy into the half-demon.
The fur on his tail regains its blue iridescent sheen, scars fade ever so slightly, and Rin smiles. It seemingly affects those around him, making them feel safe and content, as if Rin was physically handing them his happiness. In a way, he was.
It leaves everyone, even Yukio, puzzled about how such beautiful and dangerous flames can also be so gentle and purposeful.
They think it’s probably because of the living bundle of positivity that controls them and bends them to his will.