User blog comment:Nomad27/Predictions of what will Occur in Volume 10./@comment-69.125.166.95-20151219223908/@comment-5907785-20151228064930

Considering Momonga's tendency to not give his subs overwork, It might be another person other than Cocytus (Lizardman) or Demiurge (Diplomacies with The Empire), Albedo (Searching for other SB) or Shalltear. Sebas is watching over Tsuare so Mare or Aura is the most likely.