The ruling on a woman who becomes pure from menstruation, her husband has intercourse with her, and then she sees blood

Question:
May Allah reward you. The questioner from Yemen says: If a woman has her menses for the number of days she usually does, and during this period she becomes pure, and she remains pure during the days of purity until her husband has intercourse with her, and immediately after the intercourse the blood returns anew, what is the ruling in this case? May you be rewarded. And what is required of the husband and wife?

Answer:
If the purity was complete, meaning the days of the cycle were completed, and then she saw complete cleanliness and complete purity, and she performed the ritual bath and her husband had intercourse with her, then this blood that came to her is not considered to be of any account; it is considered blood of corruption. But if the days of her custom had not ended, and she only saw purity and cleanliness during the custom, and she performed the ritual bath and prayed, then it is disliked for her husband to have intercourse with her, fearing that the blood might return. If the blood returns, it is menstruation, because it is within the days of her custom. Yes.
Or it is menstruation, and her husband has had intercourse with her while she is menstruating. So he must repent to Allah Mighty and Majestic, and he owes an expiation. This means he gives in charity a dinar of gold or half of it, meaning a mithqal of gold, or half a mithqal, or the equivalent of that in paper money. They give it in charity to the poor. Yes.