Infiltration, Unarmed Combat, Swordsmanship with the Blood Moon Blade
"Tenzei" is not a true name; it is merely the title of the generation of the warrior-cult Blood Moon Monks that he belonged too; First-Blood also implies where he ranked among them. The Blood Moon Monks are considered to be a dangerous band that are said to take in children, whether from the streets or their own cribs, and train them into the efficient hand-to-hand terrors, believing themselves divinely inspired by both the Spirits of the Moon and Violence. Their stated goal is to stand ready for, "The Coming", whatever that is. In function, they are little more than hired swords and assassins, those employed for public and brutal executions rather than subtle ones that could be passed off as natural causes. Naturally, it is illegal for the Blood Moon Monks to operate in Eraia, or anywhere for that matter, and naturally they do so anyway. First Blood Tenzei is a somewhat experienced warrior, having been part of the second most recent "graduation". He is guarded, sarcastic, and none-to-happy about being Blood Moon Monk, being one of the children snatched from a crib, a fact not kept secret from him. Still, he feels like he has nowhere to go, and should Princess Idana wish a Blood Moon Monk to aid in her mad quest, she could do little better, and far, far worse than a First-Blood...
I hope this fits in with the theme you are trying to go for here.