Is KOII a profit sharing token (PST)?

Yes, if you upload/register an NFT through the koi.rocks portal, Koii Network will store your NFT on Arweave and mint a unique Profit Sharing Token (PST) for your NFT.

You will earn attention rewards in the form of $KOII if you own 100% of your NFT PSTs. After you redeemed your NFT and minted your PSTs, if you chose to sell 50% of them to buyers on Verto PST exchange (https://verto.exchange/), then you would receive 50% of the attention rewards for your NFTs.