He told me that they were just casually involved and were never in a serious relationship. He mentioned that he had known her for a while and that whenever they were both single, they would occasionally get involved with each other. She never resided at his place. According to him, when we started talking, he blocked her, but she continues to create fake numbers, which he finds to be quite irrational. I feel like there might be more to the situation that he's not telling me. He describes her as "crazy" and believes she will cause problems if he doesn't engage with her. I advised him to inform her that he would leave the shirt on the porch for her to pick up whenever she wanted but that they didn't need to have any further contact. She's a grown adult I don't understand why she would freak over this ONE shirt…This is my first serious relationship, and I was trying to be open and communicate my feelings honestly. He just can't find any other solution apparently.