Wrong methodology. First Circles have very little to do with the Yozis they ultimately descend from. Angyalkae, the living harpists, are from Adorjan; the Silent Wind. Neomah, the demon courtesan flesh-crafters, are from Malfeas; green fire and burning rage and kingship. Agatae, the beautiful wasp-steeds, are from Cecelyne, the bitter Lawgiver desert-goddess. None of these have obvious relationships to their Yozis; this is because Yozis do not make First Circles, as a rule.
If you want a First Circle to do a specific job, think about what Second or Third Circle would make a living tool - which is what First Circles are - to do that specific job. If there aren't any obvious ones that jump out at you; invent one.
Gah. That's all true enough, and I should have thought of that. Honestly, though, the suggestions of 'Demon Spiders' are fair ones, although a dedicated Kidnap Demon would probably have some ability to escape through non-mortal means, while I'm not sure most Demon Spiders do.
I don't think there are any canonical Second Circles who'd really design something like that, though.
...On a side note (I may be on a Hell-related ideas train right now) I'm wondering what Favored Yozi would be most useful to a Slayer who wants to call out the Gods for the
shitty state that Creation's in right now. The Yozi might not be much better- none of the alternatives seem any better- but in her view, the gods need a dammed wake-up call, and if she's the one who has to deliver it, then she'll do it!
*coughs* Anyway, I was considering Kimbery (have her be from the West, with a specific beef against the Storm Mothers- one of which maaaay have been involved in how she ended up Exalting), but I'm not sure she'd entirely fit in terms of mental stuff (although Hate Springs Eternal might work...)
Basically, although I'm moving beyond that, she's partially inspired by Asura's Wrath in terms of "There are things wrong with the world, and I am
furious about that"