I think this was a single chapter sized story but could be wrong about this if it is part of a larger manga

A woman (i think she worked at the hospital which would make her probably a nurse) is being raped by a patient in a hospital (location appears to be a hallway if i remember correctly). In the beginning she protested but the end result is pretty standard because the woman starts loving it. From the translation i remembered that the patient has had sex with the woman before but she stopped with the reason that somebody has started living together with her (i believe it was her little brother but not sure about that one) and did not want to continue what she was doing.

After this the woman also starts having sex with the patient in her apartment (more specifically her bedroom) while her brother is in another room

In the final part the brother and woman are having sex (in a hospital bed if i remember correctly). The patient is looking from the a small opening in the door and if i remember the translation correctly, he somehow set up the woman to have sex with the person (the brother) in the hospital bed.

From the final text bubbles i think it was revealed that the patient was critically ill and will not have very long to live