For you that know Circle of Ouroborus, this is mostly just more of the same. For those that don't, expect raw black metal, occultist themes, alienation, depression and enough post-punk to shake a stick at. They base themselves heavily on haunting vocals, slowly developing riffs and Joy Division inspired basslines, an influence they certainly won't deny. Vocalist Antti Kelmi surely takes cues from Ian Curtis' well known drones, taking it into a raspy croon more than fitting for this "post-black" duo, extending the atmosphere to a otherworldly setting. They also point to the fact with their fantastic cover of the classic "She's Lost Control" on their first full-length album, Shores.
Crooked Necks (of whom I knew nothing about before this) are a wonderful pairing, as they also do well to mix their various post-punk and black metal influences, although I should admit, it is a bit more transparent. Although this is what certainly sets them apart, and partially why I enjoyed their side like I do, they do less to blend what links the styles, and rather mesh what sets them apart. Rhythmic, "happy" tunes, spliced with harsh vocals and the occasional thick distortion creates a juxtaposition of sound that is both inviting and jarring.
To say the least, it's unlikely you'll find anything quite like it. You could compare the atmosphere of Circle of Ouroborus to the likes of Urfaust or Nuit Noire (both appearing on split records with CoO), and you could compare Crooked Necks to the new wave of "blackgaze" or whatever other name is applied to these recent post-punk/shoegaze inspired bands such as Amesoeurs, Dopamine, and Shyy, but it's hard to say that anything is quite like the mix you'll find with these bands.