The pair is virtual. vCASH is a real stablecoin. vCASH is technically backed by all the assets in the pool. However, it’s more accurate to say that it is backed by the sell function because when a user sells into vCASH it mints the physical stablecoin. In essence, vCASH is backed by the liquidity itself, not the assets. vCASH is only backed when there is a positive vCASH balance in the pool. Trustless listing pools cannot go below 0 for vCASH balance.