Man, if you're craving some good ol' Vox x OC romance, you gotta check out Archive of Our Own (AO3). That place is a goldmine for fanfiction of all kinds, and the tagging system is a godsend when you're hunting for specific pairings. I once spent an entire weekend binge-reading this slow-burn Vox x OC enemies-to-lovers fic that had me screaming into my pillow at 3 AM. Wattpad's another solid option, though you might have to sift through more amateur writing to find the gems.
Don't sleep on Tumblr either - some of the most creative Vox x OC AUs live there, with authors posting drabbles and headcanons that'll live rent-free in your brain. And if you're into darker themes, I stumbled upon this breathtakingly angsty Vox x OC soulmate AU on Quotev that still haunts me months later. Honestly, half the fun is digging through different platforms to uncover hidden masterpieces.