relentless -
not to be placated or appeased or moved by entreaty; "grim determination"; "grim necessity"; "Russia's final hour, it seemed, approached with inexorable certainty"; "relentless persecution"; "the stern demands of parenthood"
continual occurring without interruption; chiefly restricted to what recurs regularly or frequently in a prolonged and closely spaced series; "the continual banging of the shutters"
