Your question is like asking “when is a corpse putrid?” Many tracts are immoral in the sense that the reader is effected or influenced in a way not in the interest of their Soul propensity. But that is a mater of maturity and technique, and the clear ability, or not, to apply critical thinking. Much of what gets labeled as immoral earned that because of the emotional loading the material or whatever had for the beholder. That is similar to the adage about where Beauty lies. And sometimes beauty lies.
But to the pathologist, tracing the ways of inquiry that lead to clear insight as to the answer to a riddle, the matter at hand is indifferent. It is simply what is before the attention for analysis. So the question has, as well, much to do with one’s intent in reading. Is it to be entertained? Or to feel sensations or emotions sparked by scenarios before one’s mind’s eye? Or is there a reason to understand the underlying patterns or motives of the presentation in order to gain competence?
This is why we are enjoined to stand porter at the gate of thought, lest the enemy enter. One can habituate to comparing the suggestions of daily life in whatever arena, even reading material, to an Ideal. If it doesn’t match up, or doesn’t lead to freedom, then why entertain it? A lot of morality debates are sidestepped simply by asking “Does this serve the intention of my salvation?”
