Ok, so I've been cycling through "Spell Suggestions" and decided that the term "Half-Demon" needs to be addressed and made already.
To start off lets address WHY?
Most people want to become "Half-demon" because of some urge they feel inside to be evil. Not only that, but people also expect to change physical form or even manifest power from the underworld to destroy enemies(gain strength, speed, ect).
THIS ALL NEEDS TO BE PUT AWAY.
Becoming a Half-Demon is a spiritual thing that needs to be put as such:
A Half-Demon is a Human of Evil intentions and who's chakras' are either off balance or filled with Negative energies (this usually reflects onto the physical body depending on how unbalanced or negative the Human is).
To Be Continued... Part 2 "How"