Monster Tinder

[Amaterasu]

Vision

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Shirohebi (White Snake)!

Why not a regular lamia? Because Shirohebi has more waifu factor. Don't try to deny it Vision, you need more waifu in your life.
I know little about Vision but it is my understanding that he's an android who is mentally a human - not just simulating it, but really one. A human with a synthetic body. He's been married to a woman so we can safely assume that he's into girls. He may also be into humans more than monstergirls, but this is Monster Tinder - no humans here!
This match is more based around Shirohebi, Vision's match, than around Vision himself, though a few reasons can be listed as to why they'd be a great couple: first of all Shirohebis tend to be mikos - shrine maidens - to benevolent deities. Vision may not be a god but he's certainly a benevolent person, seeking justice and happiness for the world... even if the cost may be great. Shirohebi is not a fighter, though certainly not defenseless either, but she too seeks to bring luck and happiness to the world. And to be happy herself.
Now, lamias have one major problem: their tails. Or entire lower body, in fact. Humans are fragile creatures, and even among monster-people there aren't many that can deal with the immense physical strength and weight that said tail brings. Better leave the weight out, but an adult lamia could crush a car if she wrapped her tail around it, no problem. And when they get affectionate (not necessarily sex, cuddling works too!) they wrap their tail around their partner and restrain them tightly. They often don't even realize that they're doing this. While they have great control over their tail it may happen that they constrict reflexively when tensing up for any reason, for instance when getting shocked or surprised from an outside influence. That brief moment of constriction is enough to crush numerous bones in their partner's body, and the lamia will be horrified about it.
But, Vision. Here we have a being made out of one of the most durable materials on earth, capable of making himself even more durable AND capable of phasing himself out of a tight bind - literally - if things get hairy. Car-crushing muscles wouldn't be able to dent him. He'd probably comment on it, but otherwise just appreciate the tight hug, then phase his arms through Shirohebis restraint to hug her back, or pull her into a kiss.
Also, for those who can endure or don't mind the tail restrainings, lamias are among the best partners that you can have. They are incredibly cuddly and affectionate, very caring for their partner - though unfortunately not the best cooks because as carnivores their sense of taste is not very sensitive - and during the winter will be needing constant body warmth so as to avoid going into hibernation. They are a little clingy and needy, yes, but they can learn to be independant too - they're humanly smart and thus able to understand if their partner needs a little distance once in a while. Shirohebis in particular can become as devoted to their partner as they are to their chosen deity. Which is a lot. The only worry is that Vision might get overwhelmed by all the cuddlings.