Bakeneko Cat

Devil's Sight. Magical darkness doesn't impede the cat's Darkvision.

Keen Hearing and Smell. The bakeneko cat has Advantage on Wisdom (Perception) checks that rely on hearing or smell.

Incorporeal Movement. The bakeneko cat can move through other creatures and objects as if they were Difficult Terrain. It takes 2 (1d4) Force damage if it ends its turn inside an object.

Magic Resistance. The bakeneko cat has aAdvantage on saving throws against spells and other magical effects.

Shapechanger. The bakeneko cat can use its action to polymorph into a Small or Medium humanoid (usually an old or beautiful female), or back into its true form. Its statistics, other than its size, are the same in each form. Any equipment it is carrying or wearing isn't transformed with it. It reverts to it's true form if it dies.

Innate Spellcasting. The bakaneko cat's spellcasting ability is Charisma (spell save DC 13). The bakeneko cat can innately cast the following spells, requiring no material components:

At will: prestidigitation, minor illusion, hex, silent image

1/day each: bestow curse, charm person, hold person 

Bite (Cat form). Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 6 (1d4 + 4) piercing damage. The target must succeed on a DC 13 Constitution saving throw, taking 10 (3d6) Poison damage on a failed save, or half as much damage on a successful one. 

Claw (Cat or Humanoid form). Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 6 (1d4 + 4) Slashing damage.