I’m a bit confused about the Ooshima Tomo / Towa situation. They sound like they’re saying they go by a different name depending on the work, but aren’t they different people...? I dunno, is it related to their Sweet Pea / Cocoa Break aliases.
Perhaps it should have read " We usually publish... under different circle names?" It's entirely possible that the original Japanese doesn't specify who does the publishing, or how many there are of anything.
I'm also confused by the line "Thank you for forgetting this book," by the way.