Yep that is a BLE device added by an app. I do not know what device that would be, but go to Settings > Privacy & Security > Bluetooth, and turn off permissions for any apps one at a time until it is removed to get a better idea what it could be. Thank you for the redactions in your Screenshot.
It could be your Libre, and when you turn off the Bluetooth permissions for the Libre app, it will be removed. You can enable permissions again. If you are able to turn them off on the device, you may also want to try that to see if it disappears or disconnects.