Vouivre

One half of this creature is a nude woman, and the other is the front end of a slithering, winged dragon.
 

Vouivre (CR 12)

Large Monstrous Humanoid (Aquatic)
Alignment: Chaotic Evil
Initiative: +5
Senses: Darkvision 60 feet; Perception +17
  Speed: 30 feet, Fly 40 feet (poor), Swim 50 feet
Space: 10 feet
 

Defense

Armor Class: 27, touch 10, flat-footed 26 (+1 Dex, +17 natural, -1 size)
Hit Points: 152 (16d10+64)
Saving Throws: Fort +9, Ref +11, Will +14; +4 vs. mind-affecting effects
unwavering mind
Immunity: cold
Energy Resistance: fire 10, sonic 10
 

Offense

Melee: bite +20 (3d6+4 plus Grab), 2 claws +20 (2d6+4/19-20), 2 wings +14 (1d8+2)
Reach: 10 feet
  Special Attacks: Breath Weapon (30-ft. cone, 8d6 fire, Reflex DC 22 half, usable every 1d4 rounds)
  Spell-Like Abilities (CL 13th; Concentration +17):

Statistics

StrDexConIntWisCha
19 (+4) 13 (+1) 18 (+4) 11 (+0) 14 (+2) 18 (+4)
Base Attack Bonus: +16
CMB +21 (+25 Grapple)
CMD 32 (can't be tripped)
  Feats: Critical Focus, Deafening Critical, Great Fortitude, Improved Critical (claw), Improved Initiative, Iron Will, Weapon Focus (bite), Weapon Focus (claw)
  Skills: Bluff +20, Fly +6, Intimidate +15, Perception +17, Sense Motive +10, Stealth +12, Swim +12
  Languages: Common, Sylvan
  Special Qualities: Amphibious, snake empathy

 

Special Abilities

Snake Empathy (Ex)

A vouivre can communicate and empathize with snakes. It can use Diplomacy to alter such an animal's attitude, and when doing so gains a +4 racial bonus on the check.

Unwavering Mind (Ex)

A vouivre gains a +4 bonus on saving throws to resist mind-affecting effects.
 

Ecology

Environment: Temperate Forests, Lakes, or Rivers
Organization: solitary or harem (1 plus 4-10 snakes)
Treasure: standard

  A vouivre is a deceptive and monstrous predator that looks like a humanoid woman from the waist up and the front end of a green-scaled dragon from the waist down. It shuns the company of its own kind, preferring evil fey (particularly water-dwelling ones such as nixies) for intelligent conversation and mundane snakes for companionship.
  A vouivre is 12 feet long from head to head, weighs 500 pounds, and can live 200 years. Vouivres make their homes in small caves near calm waters. They like to decorate their lairs with shiny coins, jewelry, and bright silks. One might place some of its treasure in the water outside to lure in curious humanoids, and bathe in these waters as a further enticement, hiding its reptilian half until prey is within striking distance.
  Because a vouivre can breathe water or air (from either head), it often grabs a creature, then retreats underwater to wait for the opponent to drown. It prefers humanoid flesh, but will feed on any available warm-blooded prey. Vouivres have an affinity for music, and their magic is often accompanied by singing or subtle musical vibrations from their scales.
  When a vouivre dies, its dragon head disgorges a 2-foot-diameter glassy egg. After around 6 weeks, the egg hatches into one or two vouivres, which take 7 years to reach maturity. These offspring resemble humanoids the mother has eaten, so it prefers to feast on attractive and strong victims. The young also adapt to the appearance of nearby reptilian creatures.