Taken from the Creature Codex
This loping creature appears as a cross between a hyena and a great ape. Its long arms end in clawed hands rather than paws.
Kerits, or beast demons, are savage monsters that delight in the slaughter of innocents. They are created in the Abyss from the souls of chaotic evil mortals who intentionally lived like animals and descended into a live of savage violence. Kerits are popular guardians and totems among evil humanoids like orcs and gnolls, which see the kerit as an inspirational figure.
On the Material Plane, most kerits are solitary, but in the Abyss they cluster into huge hordes at the behest of stronger demons or to protect against their depredations. They have a dim and cunning intelligence, but delight in masquerading as a simple animal. Nothing pleases a kerit more than a community gripped in fear and paranoia, killing relatively harmless wildlife and driving itself into a frenzy between attacks by the beast demon.
Kerit CR 5
CE Large outsider (chaos, demon, evil, extraplanar)
Init +6; Senses darkvision 60 ft., Perception +11, scent
Aura frightful presence (30 ft., DC 15)
AC 16, touch 11, flat-footed 16 (-1 size, +2 Dex, +5 natural)
hp 51 (6d10+18)
Fort +5, Ref +7, Will +7
DR 5/ cold iron or good; Immune electricity, poison; Resist acid 10, cold 10, fire 10; SR 16
Defensive Abilities uncanny dodge
Speed 40 ft., climb 30 ft.
Melee bite +9 (1d8+4 plus grab), 2 claws +9 (1d6+4)
Space 10 ft.,; Reach 10 ft.
Special Abilities eat brains,rend (2 claws, 1d6+6)
Spell-like Abilities CL 6th, concentration +8
3/day—greater teleport (self plus 50 lbs or objects), invisibility
1/day—haste (self only), summon (level 3rd, 1 kerit 40%)
Str 19, Dex 15, Con 16, Int 7, Wis14, Cha 14
Base Atk +6; CMB +11 (+15 grapple); CMD 23
Feats Improved Initiative, Nimble Moves, Power Attack
Skills Acrobatics +11 (+15 jumping), Bluff +8, Climb +12, Perception +11, Stealth +7, Survival +8
Languages Abyssal, Celestial, Gnoll, telepathy 100 ft.
Environment the Abyss
Organization solitary, pair, pack (3-8) or horde (10-40)
Eat Brains (Su) As a full-round action, a kerit can make a coup de grace against a fallen opponent and devour its brains. The body is mutilated such that a raise dead or other effect that requires an intact corpse will not work. If a kerit successfully consumes brains, it gains a +4 enhancement bonus to Strength and fast healing equal to the number of HD the victim had. This bonus lasts for 1 minute per Hit Die of the kerit (6 minutes for the average kerit).