Seeing the black book covered in chains which was engulfed in black flames that floated in front of Marcus, Daimon couldn't help but frown for a second.
'A promise rank treasure… no, it feels more like a spell or more accurately an innate ability, I didn't even know that there were promise rank abilities', he thought as he felt the threatening aura radiated by that book, which was both corporeal and ethereal at the same time.
It felt like a hybrid between a promise level magic treasure and a grimoire like the ones Daimon and the girls have gotten through the "Fragments of Laplace".
Promise rank is not exactly a "level" by the way, it's unrelated to the realm of the object in question, so it would be more accurate to call it the capacity of something to automatically grow alongside their owner, just like the Trident of the Storm which was lucky to have its existence spared by Narasha, since it is not a sword unlike Adam's treasure.
