She's snatched up in its tentacles before she even really registers what's happening, and the very first thing it does after she's caught is shove one down her throat. Its slime is surprisingly sweet, and makes it slide down with ease, interrupting her barely even begun 'chirr.' Her first unthinking instinct is to bite, but it's forced her mouth so far open it's painful, and a combination of the thickness, strength, and durability of the tentacle means this attempt goes nowhere. She just doesn't have the leverage or the jaw power.
There's a lingering sickeningly sweet stench in the air, and she's sure that either it, the slime on this thing's tentacles, or both, is some kind of aphrodisiac, because. .... Because. Look, not that being snatched by a giant tentacle monster isn't totally hot, but in her current state she'd half expect herself to find another one of its tentacles and impale herself on it out of sheer lust. Which, for the record, is not something she'd think too seriously about in most circumstances, even this one. A tentacle slides its way up her back to force it to arch before its end begins gently playing with one of her breasts, and she can't manage to keep herself from moaning and shivering in anticipation. Oh, fuck, this is bad—
—What does it want, can she tell, is it going to keep her—?
Her intelligent captor gives an amused growl that's almost a chuckle as it pries open her resisting legs. The tentacle in her throat squirms in a way that shouldn't feel that nice (except it definitely does) and elicits a little whimper. No, it doesn't want to keep her. But the little mage will bear its seeds, and it will be sure to savor every delicious moment it has this naïve little treat in its grasp. She will be an excellent host for them, and its spawn will hopefully dwarf it in power. After all, she's so rich in mana, and so spirited! Yes, she'll be perfect to impale on its seed bearing member. To prepare her, or perhaps taunt her, it rubs it oh-so-gently against her cunt, covering it in aphrodisiacal slime that makes it tingle pleasantly. She notes, in some backwards corner of her mind, that it is far too big to go in easily, and definitely not without a small degree of pain. It knows it's going to hurt her. It's looking forward to that, too.
That's about when she finishes silently activating her favorite four runenodes, throwing as much mana as she can behind the blast to make it as big as possible, aimed (mostly) outside of herself. It hurts like a bitch, but it is nonetheless very satisfying. Fuck you, monster thing—!
This time, the monster makes a sound that is definitely a laugh. The fire.... absolutely burned it, but its regeneration is as thorough as hers. And it's sturdier and has significantly more mass. It gives her a moment to take in this horrifying revelation and realize the seriousness of her predicament, tentacles slithering up and down her body to stimulate her as it waits. Then its tentacles tighten around her thighs to hold her steady and it thrusts inside her and, and.
Sexual organs should not be this large.
To say it hurts going in would be an understatement. It tears her open, and its slime stings and burns into her through the rips it made, and, and yep it is definitely an aphrodisiac, because it's for sure now in her bloodstream and oh fuck she wants more right now. This is so much better than the tentacle pit, and she hasn't even climaxed. Just being impaled on something this large and powerful and thick is mind-blowing and, and then it withdraws. It withdraws, and she can't help but whine because no, no come back, she was so close, it was so good. The perfect mix of pain and pleasure and she hates how much she enjoys this. Hates how much she wants it to continue.
Turns out, it was just waiting for her regeneration to knit her back together. So it could rip her open again. Since she enjoyed that so much.
Oh.
Its head reaches further inside her than it did the first time, and arrives at her cervix. Then, it. Keeps. Going. The only sane part left in her head that isn't screaming yes pathetically notes that this shouldn't be anatomically possible. Too bad, it's happening anyway. And then she no longer has the presence of mind to make snarky commentary or try to cast anything. Even though she still desperately wants to burn it to cinders. Her climax is as intense as anything she'd had while trapped, but it's all the trappings around it that make it better. She'd never been toyed with on a personal, emotional level like this before. Never raped by anything this thick before, never out in the open where she can see freedom is just right over there, where anything could show up and see her being thrust into by a goddamned monster and shaking like a leaf and whining for more. Never felt this at the mercy of a great and powerful being with a will and lust and delicious sadism.
The monster thinks she's beautiful and fascinating, and that it's so lucky it found her while she was new and vulnerable. It purrs it, across their connection, along with praise at how good she feels. Affectionately, it pets her, and she can barely notice through the pleasure but it's so nice to feel anyway. Why does she like this. Why does she want this.
It doesn't really matter. She's too far gone to think about the whys. All that's left is a bitter, aching despair at falling back into the familiar pattern of being used. Of enjoying it.