Before I begin, I want to open by saying I really respect how you're incorporating parts of the world other people have made into yours!
After that, first thing is super minor, but the word 'see-through' just sounds a bit kiddish to me and doesn't really match the tone you seem to be going with. If you don't know what a certain word is, I typically go to
thesaurus.com, but other things that would work are things like clear or transparent. I'm not gonna nitpick every word, but I'd personally avoid see through, unless I'm using it like a verb. Like, "I can see through your shirt/plan/you," unless your speaker is highly informal or fishing for words. Again though, super minor.
Next, have you put any thought into using bold or italics into your works? It can really power things up, especially dialogue.
"Why did you kill him?" The hooded person asked slowly, the barely contained anger evident in his voice.
"This has nothing to do with you," Erik countered.
"Why…Did…You…Kill…Him?"
"He…did something he shouldn't have," Erik answered, eyes narrowed.
"You mean exposing the greed and corruption in his workplace?!"
"So he told you about that," Erik's frown growing even deeper, "People paid for his death, I obliged but seeing as you know too I have to put you down," he gave a non-committal shrug as if to punctuate his statement. Better to come clean than to try and needlessly justify his morally questionable actions, it was much less of a hassle.
The hooded stranger grit his teeth, the wood in his hands creaking from his tightening grip, "You, its people like you who are the reason why the world is so messed up. You people who completely disregard others to further your own ambition, greed, and pleasure. The reason why innocent people suffer is because of those like you."
"Why did you kill him?" The hooded person asked slowly, the barely contained anger evident in his voice.
"This has nothing to do with you," Erik countered.
"Why…Did…You…Kill…Him?"
"He…did something he shouldn't have," Erik answered, eyes narrowed.
"You mean exposing the greed and corruption in his workplace?!"
"So he told you about that," Erik's frown growing even deeper, "People paid for his death, I obliged but seeing as you know too I have to put you down," he gave a non-committal shrug as if to punctuate his statement. Better to come clean than to try and needlessly justify his morally questionable actions, it was much less of a hassle.
The hooded stranger grit his teeth, the wood in his hands creaking from his tightening grip, "You, its people like you who are the reason why the world is so messed up. You people who completely disregard others to further your own ambition, greed, and pleasure. The reason why innocent people suffer is because of those like you."
Next, when you introduce new skills, if you slow down rather than state it, it'll help your reader follow you a great deal more.
I think you did it really well here:
Kassaran unsheathed his second blade completing the "Twin Blades of Drakmar," the swords were identical copies of each other as the name would suggest. Double edged with an odd indentation running down the center of each and glowing with holy power. The two stared each other down briefly, Kassaran's glowing gold against Scarlet's cold amber, before charging at each other. The two locked blades the nephilim putting all his current strength into the attack yet was being pushed back. His eyes went wide, the knight was much stronger than he anticipated. The angel broke off by raising his foot feinting to kick the knight, which she fell for by jumping back to gain distance.
But it was a bit lacking times like this:
Kassaran stepped back and followed Erik's lead, jumping through the window. On the way down the half-angel caught himself by unfurling his white feathery wings to soften his landing. His injured leg thrummed with a dull pain but was nothing he could not ignore.
All in all though, I really enjoyed the story! Looking forward to seeing Yukari in action!