Clary, Jace, Simon, and Alec have ventured seemingly past the point of no return to save the ones they love and the entire race of Shadowhunters- the demon realms. But what if City of Heavenly Fire had ended differently? How would their whole world change if they were prisoners of Sebastian before his defeat? How can Clary cope with being her brother's play toy? Clace, Sizzy, Malec, and, yes, Clabastian. Nothing too explicit.