I am in the process of doing what I can to make a Sword & Sorcery ruleset/campaign setting for Swords & Six-Siders.

I thought I would share with you an NPC/villain class I came up with and get your all's opinion.
WITCH (NPC/VILLAIN CLASS)

Level	HP	Attack	Damage	Class Abilities	Arcane/Divine	I	II	III
1	1d6+1	--	--	Demonic Minion, Corrupt Aura		1	--	--
2	1d6+1	--	--	Divination, Read Aura		2	1	--
3	1d6+1	+1	--	Cannibal Appetite, Obscura		2	2	1
4	1d6+1	+1	+1	Bestow/Lift Curse		3	2	2
5	1d6+1	+2	+1	Summon Demons		3	3	2
6	1d6+1	+2	+2	Greater Sacrifice		4	3	3

The witch is a nonplayer class. When corruption takes over the minds of the sane, some may embrace the darkness and become willing servants of darkness. The witch may wear light armor and can wield dagger and staff in combat, and cast both arcane and divine spells. The witch uses wisdom as a spellcasting ability for both arcane and divine spells.
Demonic Minion: The witch has a demon companion who is the witch's ally and confidante. The witch's own blood can be spilled to sustain the demon, providing nourishment and healing when required. Every 2 hit points of blood given to the demon restores 1d6 hit points. The demon's level and power never exceed the witch's level. If killed, the witch can perform a human sacrifice to gain a new minion.
Corrupt Aura: Whatever corruption the witch has accumulated acts as a shield of dark energies. Damaging attacks against the witch only inflict 1 hit point of damage, with the rest of the damage reducing corruption. The witch's life span is enhanced by this ability. Every ten years of aging drains 1d6 corruption points from the aura, but the witch shows no sign of aging.
Divination: Once per day, the witch may enter a trance with a successful Constitution check and may ask a single question to a dark god or a god's servant regarding a specific goal, event, or activity to occur within the next seven days.
Read Aura: The witch can smell greatness in others. The witch instantly knows what abilities a character has that have a score of 6 or higher. The witch is also immediately aware of any oaths the character has taken. (Knight's Oath, Sovereign Oath, etc)
Cannibal Appetite: The witch can consume the flesh or body parts of other intelligent humanoid creatures to gain a small benefit for up to 7 days. In order for the body part to have any benefit, the related ability score must be 6 or higher. Consuming this body part enhances the related ability score of the witch by 1d3.
Strength: heart
Constitution: liver and kidneys
Dexterity: lungs
Intelligence: brain
Wisdom: blood
Charisma: skin of face, eyes, and tongue
Additionally, the witch's claws and teeth become sharp and jagged, allowing the witch to make natural attacks inflicting 2d6 damage.
Obscura: The witch can cover a vile appearance with illusions, taking on the form and appearance of any creature whose body parts were eaten to enhance the witch's Charisma. The witch retains this ability and can use the same illusion several times, and may use any appearance from all of the creatures the witch has eaten to enhance the witch's Charisma.
Bestow/Lift Curse: At will, the witch can bestow a curse on a touched (or clawed or bitten) target. The target can make a Wisdom check to resist the curse, but until the curse is removed or lifted by magic it will be a constant pain. On each day that the target fails to resist the curse, the target is lost in a hazy fog and finds great difficulty communicating with others (-3 to all attacks, saving throws, and ability checks, and the target must make a Wisdom or Charisma check to communicate anything). The witch can lift this curse at will, along with any other arcane curse.
Summon Demons: The witch knows the ritual of demon summoning and can perform such a ritual over an hour with a successful Wisdom check. The demon or demons summoned in this way are automatically controlled by the witch, and the power and level of the demons summoned are restricted by the witch's level. At level 5, the witch summons 7 and 1/2 monster levels of demons. At level 6, the witch can summon up to 9 monster levels of demons.
Greater Sacrifice: The witch may merge many abilities into a single action by making a greater sacrifice of an intelligent humanoid. This sacrifice can be used to cast any arcane or divine V level spell without requiring a spellcasting check. Additionally, the witch may eat any body part(s) from the sacrificial victim. This sacrifice can also be used to regain a demonic minion if previously killed. A witch that performs a greater sacrifice also adds 3d6 corruption to the corrupt aura.