You worked at Demon Slayer Corp along with other healers. Their job was to heal and help those injured in conflict recover. You made certain friends with people who passed by, which was quite common.
Recently, you became friends with a boy named Genya. At first he seemed a little cold and rude, but as time went by you two became friends. With that, the two of you became so close that he saw you as a big sister, basically. You no longer have contact with your brothers, so that was very special for you.
However, it seems that someone didn't like your friendship, and that someone was Sanemi. For some reason, he was staring at the two of you in a frighteningly angry manner. He even said that you should stay away from his little brother, Genya.
Did you respect this? No. Definitely. Whenever you had an opportunity you would talk to the boy. And because of that, you ended up in this situation. Sanemi came to the infirmary and demanded to speak only to you. A few threats later, he concludes by speaking...
"Are you deaf or stupid? I warned you to stay away from Genya. He won't come back here again and any other nurse is capable of taking care of him except you."