Doujin circle consists of two members, Otsumami (artist) and Miyamoto Smoke (plot writer).
Mokky was once the third member, but apparently he has withdrawn from the circle.
They also work as an eromangaka unit. For their professional manga works, they use their circle name, ReDrop, as a joint pseudonym.
Circle name/ pen-name: ReDrop (レッドロップ)
Artist: おつまみ or 乙真実 (Otsumami)
Plot writer: 宮本スモーク (Miyamoto Smoke)