PoS-R is an project that proposes a blockchain-based stock exchange system where validator selection is driven not just by wealth, but by behaviour. The core idea is a custom consensus mechanism Multi-Dimensional Proof-of-Stake with Reputation, that scores validators across five dimensions (accuracy, speed, integrity, regulatory compliance, and stake consistency) and uses those scores alongside staked capital to decide who verifies each trade. Built with Solidity smart contracts on Ethereum and a live React.js dashboard, the system was validated through a 10,000-transaction simulation that detected collusion patterns no existing PoS system can identify directly addressing the kind of preferential behaviour seen in the 2015 NSE co-location scandal.