Bleeding from the anal area can be due to rectal_bleeding or Gastrointestinal Bleeding
(click the links above for more information)
Another possible reason could be hemorrhoids as well.
bright red blood usually suggest that the blood is coming from the lower part of the GI tract (large bowel or rectum).
If there is more than 2 tablespoons of blood, she needs to be seen. Otherwise, she can also get a mirror and try to look around the anal area and see if she can see any hemorrhoids or anal fissures. If unsure, do have her follow up with her doctor.
With you saying like a covering, I'm not sure if it's mucous: Which the mucous may be coming from the intestinal tract. Which could be due to inflammation, infection, IBS, colitis, anal fissures.
It could be a combination of issues, such as the IBS and anal fissures or hemorrhoids etc.
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