The Calamarain are a sapient spaceborne species with bodies made out of swirls of ionized gas. They are one of the many species to have fallen victim of Q's mischievousness in the past, and when he was stripped of his powers as a punishment by the Q Continuum, the vengeful Calamarain somehow became aware of it and attempted to kidnap Q from the Enterprise, where he had asked for asylum.
As Lieutenant Data saved Q, the former omnipotent realized his own cowardice compared to these mortal entities, and escaped in a shuttlecraft to lure the Calamarain away from the Enterprise so that others wouldn't be in danger. This noble act ultimately convinced the Continuum to accept Q back as one of them and return his powers, after which he briefly threatened to torment the Calamarain, but under insistence from the other Qs instead transported them away without harm.
Despite the Calamarain's hostile behavior towards him, Q claims nothing that he had done to them was grotesque or bizarre, and describes the gaseous entities as flighty and as having no sense of humor.