This is a rather unusual topic. One possible story could be that in a very strict and traditional community, a child might see a friend's mother as a figure of extreme authority. Maybe the child misbehaves in front of her and has a strange sense of expecting her to spank as a form of discipline because they have seen her be so strict with their friend. However, this is not a common or healthy form of thinking in modern society as it involves crossing family boundaries.
No, it's not normal. In most cultures, discipline is a family - specific matter. The idea of wanting someone outside the family, especially a friend's mother, to administer physical discipline is inappropriate and goes against the norms of personal boundaries and family privacy.
Well, without more context, it's hard to say precisely. 'A Mother's Revenge 1993 True Story' might involve a mother who found herself in a situation where she had to take matters into her own hands for revenge. It could be related to personal vendettas, like if someone hurt her child or violated her family's safety in 1993, and she decided to retaliate in some way.
It's a tricky topic. Some manga might handle it sensitively and offer some sort of understanding or hope, but it really depends on the execution and the message it aims to convey.
If a friend's mother wants to spank you, it's a very uncomfortable situation. First, you should try to talk to your friend about it. Maybe there's some misunderstanding. If that doesn't work, you might need to tell your own parents. They can help you figure out how to handle this strange situation.
Well, without having read it, it could be that the revenge angels are on a mission to right the wrongs that have befallen their mother. Maybe their mother was wronged by some powerful entity, and the angels, with their special powers, are out to make things even. It might also include elements of family loyalty and the struggle between good and evil in the context of their revenge.