What it is
When your token graduates to FrothSwap, the protocol mints you a RoyaltyNFT for the pair. It's the on-chain claim to the creator share of that pair's DEX protocol fees.
What it pays
Every swap on your token's pair routes a slice of protocol fees to the RoyaltyVault for the NFT holder. It accrues for as long as the pair trades. Claim whenever you like from /portfolio.
It's transferable
The NFT is a normal transferable token. Sell it and you've sold the fee stream. Whoever holds the NFT earns the royalties from that moment on. That makes a successful token's royalty stream a real asset with a price, not just passive income.
If you transfer the NFT away, you stop earning. There is no creator-address fallback.