No, you cannot refill a Mr Fog vape. Mr Fog devices are disposable vapes, which means they are designed for one-time use and come pre-filled with e-liquid. Once the e-liquid runs out or the battery dies, the entire device is meant to be discarded and replaced. Attempting to refill a disposable vape can damage the device and may lead to leaks or performance issues. If you're looking for a reusable option, consider switching to a refillable vape system or pod mod.