Name: Venus Mantrap
Type: Plant (or possibly something else—mollusc?—masquerading as a plant)
Habitat: Jungle. Dense Vegetation.
Resembles a single trap of a Venus flytrap, but on a considerably larger scale. The humanoid part, which nearly always takes the form of a beautiful naked woman, resides between the leaves and is connected to the rest of the plant via a fibrous membrane running down the spine. Catapult muscles connecting the humanoid portion to the leaf walls allow the plant to cast her out from between the leaves in order to attract and catch prey.
While the outside of the leaves is extremely hard, the inside is soft and padded and feels like flesh.
Her humanoid part functions as both a lure and centre of intelligence for the organism. She is part of a muscular apparatus that can be projected outside of the leaves in order to capture prey. Captured men (and sometimes women) are pulled back between the leaves, which then close around them.
Once her prey is caught between her padded leaves the Venus mantrap will strip them, wrap her arms and legs around them, and then get them aroused enough to have sex with her. This is aided by various aromatic and aphrodisiac oils secreted through her skin.
She stimulates her captive to multiple climaxes and then, after no more sexual fluids can be drawn from their body, she disgorges a stew of various enzymes over them. The primary component is a digestive enzyme to liquefy flesh and soft tissues. Mercifully, this digestive fluid also contains substances with both strong analgesic and aphrodisiac properties. This instils a state of heightened sensual bliss in the victim so that they are unaware of what's happening to them.
(Why? Why care? Why not just catch and digest? The one specimen we were able to interrogate said it was important that they take their prey to the pinnacle of sexual ecstasy and keep them there as they begin to digest them, but why, why, why?)
Once digestion is done the Venus mantrap will open her leaves and use the catapult muscles to fling the indigestible material such as bones far from the main plant.
The Venus mantrap, being a plant*, is stationary. She can only capture prey that stray within a narrow arc that extends from the trap opening to a distance approximately equal to the depth of the mantrap. As long as you stay outside of that arc, the mantrap can't grab you.
*(Maybe, I'm not convinced on this. The outer shell and inner flesh seem to be more in keeping with some kind of enormous shellfish. Mimicry?)
Should one of your party be caught and brought between the leaves then I'm afraid the prognosis is not good. It would take heavy earth-moving machinery to prise the leaves (shell?) open, heavy earth-moving machinery which we do not currently have access to. The outer surface is impervious to all but high explosives, and using them would likely kill her captive in the process.
The soft interior is vulnerable, but if the Venus mantrap perceives herself to be under threat she will simply retreat between and close her leaves.
Avoidance is the best strategy here. Be vigilant and don't step into her capture arc.
**upgraded to Moderate. Our men are still straying into her capture arc even when forewarned. There might be an additional pheromonal or similar component to the lure that is drawing people in despite the warnings.