Thus far the character concept seems fine, I guess, although it's still missing a background. My only immediate thoughts about the concept would be that the weapons (both of them; crank-operated crossbows are quite advanced weaponry in the current age of The Prophecy, and any weapon inscribed with permanent arcane runes is considered very valuable) must either have been very expensive or just difficult to acquire, in case he did not purchase them.
I also wonder just how much skill Felgrin would have with magic, to be able to use the runes on his dirk at all? Even presuming that the black handle would be made from iron or a metal even more magically conductive than it, like copper, it would still be much, much harder to use than a true runesword or -weapon due to the lack of the magical crystal hilt. It would require conscious effort to direct magical energy into the sword as one activated the runes, and likewise conscious maintenance of the flow of magical energy to the runes to keep them active. Having the runes would still make using magic easier than doing so empty-handed, certainly, but I feel the need to point out that it would be a lot harder to use a runeweapon without crystal hilt than one with it.