Interesting! At least it wouldn't bloat the blockchain, but just Nostr relay runners.

For the ownership (O) aspect, the transferability of NFTs on Nostr would require a mechanism to track and verify ownership transfers. This could potentially be achieved through a consensus mechanism similar to those used in blockchain technologies, where multiple relays agree on the state of ownership. The specifics of how this would work on Nostr, considering its decentralized nature and the potential for relays to go offline, would need to be carefully designed to ensure security and reliability.