No. They can be about emotional or mental bondage as well. For example, a man might be in the grip of an addiction, which is a form of mental bondage. Or he could be trapped in a toxic relationship that restricts his emotional freedom.
One danger is the risk of physical harm. If a person gets into a self - bondage situation and something goes wrong, like not being able to free themselves, they could face serious injury. For example, they might cut off circulation.
The main distinction of porn with a story genre from regular porn is the presence of a coherent narrative. Regular porn often jumps straight to the sexual action, while the story genre tries to add some kind of story framework around it. But in the end, both are adult-oriented and feature explicit sexual content.
If not literal bondage, a possible theme is the emotional bondage a mom might experience. She could be in a situation where she is constantly worried about her children's future or her relationship with her partner. The story might then explore how she copes with this emotional turmoil and finds a way to liberate herself from these negative emotions. It could also be about the mom feeling bound by her own past mistakes or regrets, and how she overcomes them.
Well, it's hard to say for sure. The concept of 'porn-like' is quite subjective. Some might consider certain novels with excessive sexual descriptions as such, but it depends on individual perspectives and cultural standards.
In many places, 18+ porn comics are considered illegal. This is because they can have a negative impact on society and violate moral and legal standards.