I've been trying to post this since Thursday and it shocks me that no one has beaten me to the punch
The anime has cast Saori Hayami as Blizzard of Hell (Jigoku no Fubuki), and Mamoru Miyano as Sweet Mask (Amai Mask). In addition, the magazine notes that JAM Project is performing the anime's opening theme, and Hiroko Moriguchi is performing the ending theme. The opening theme's CD single is slated for an October 21 release, and the ending theme's CD single is slated for a November 18 release.
The casting of Fubuki must mean that we're either getting the side chapters animated, or we're going beyond the Boros arc and right in front of Garou. Exciting stuff.