Why does it have fur???

This little guy came from my homeroom teachers dying plant, I was taking the dead leaves off and it popped off so now I’m going to propagate it. This isn’t the first time that a little piece has fallen from the plant but that piece didn’t have this “fur”?? (Also it isn’t snapped it just grew that way) I’m not sure how much it’s watered but I’m pretty sure it’s being overwatered. The plant sits on the windowsill so it gets a lot of light