In that spirit, I give you some ideas for a
I just submitted one to the Spellburn monster contest, shouted out in episode 12: Like a thief in the night. I don't want to promote too much competition with me, but hey - get on it. Details in the episode.
Also, you should take a look at the adventure that's linked to in there (The Jeweler That Dealt in Stardust). It is damn fine work.
Here is an autumn body/sex horror monster, burbling around in my psyche since I started to eat crabs after a long psycho-somatic period of pseudo-allergies
The Succubus Crab
Init -4; Atk Claw x2 melee (1d6) or fly bite +2 missile fire (range 120’, 1d3+1); AC 15; HD 3d8+12; MV 20’; Act 1d20; SP charm. SV Fort +5, Ref -5, Will +6; AL N
The Succubus Crab requires, for its sexual reproduction, the transmogrified essence of a male humanoid host. It is a lumbering 10 foot tall semi-aquatic abomination, appearing for all intents to be a tentacle-mouthed pink crab-like being with a chitinous shell and razor-sharp claws. These are the females. Buzzing around the giant clacking horrors are a cloud of males, smaller by an order of magnitude and winge'd.
In order to complete the reproduction cycle, the female sends a contingent of males to a likely victim, who is promptly stung should a succesful attack occur. Those males that miss are not fit to reproduce in any case. A small sting signals success, and the victim (usually a human male) must make a DC 15 Fortitude Save, else the reproductive essence of the male succubus crab wends its way (temporarily) into the host. Aside from the walloping sting of a bite, no further effects are immediately incurred. That said, biological changes are occuring on a cellular level in very specific tissues.
Any party encountering the female crabs are right to flee in horror and disgust - however, any stung and affected male humans are suddenly enraptured by a cloud of pheromones. The tentacular and chitnous foreparts of the Succubus Crab female appear to be a desirable member of the female human sex, writhing in erotically charged agony and ecstasy. The human male victim approaches, mates with the facial parts of the Succubus Crab, and is stunned for 1d3 rounds in utter sexual helplessness. Meanwhile, his captor carves him up into piecemeal to sustain the egg-hatching process, for the young of the species need much in the way of sustenance - at least, the females do. The males flit around like flies.
The chitin of the Succubus Crab can be shaped and worked into plates, and cured into light-weight and durable armor (AC 15, light encumbrance). They are very succulent with a sprinkling of Old Bay seasoning and sprayed with lemon, but difficult to place entirely in a steamer.