So, there actually is a story to Zach's markings

Zach is in a constant cycle of reincarnation, during which his spiritual energy is constantly building. He is, as one tends to be where reincarnation is involved, entirely unaware of this. His various lives are generally oblivious to his spiritual presence, and on the rare incarnation he is aware of any related talents - magic and such - they are unreliable, showing a tendency to either explode randomly or just fail.
The upshot of this, is that the markings on his fur are a result of this constantly growing spiritual presence: a manifestation of these energies on his body. Zach is eventually fated to become a kitsune, and his markings are the first sign of this.

Anyway, this is the theoretical moment of transcendence where he goes from regular fox to kitsune.