It's Sim's Virtue mod for BG2. The mod's creators felt that Reputation wasn't realistic enough; a party full of SOBs can still have a high reputation. So the mod creators added a new stat, Virtue. Under this mod, reputation no longer matters--evil characters can stay in a party with 20 rep, etc--but truly good deeds are rewarded with Virtue points, on a scale from 1 to 20, and they're not as easy to get as you might think.
And truly blessed or henious acts can even change your alignment. I'm testing the mod with an evil party with a Virtue of 6. Pop on over to
http://forums.forgottenwars.net and check out the House of Sim to find out more. (Don't want to do major spoils on the BG1 board.)
So yeah, it's not another NPC or trinket-laden Weimerized slaughterfest. It's a cute little mod in the same vein as Oversight and Unfinished Business, designed to make the game more detailed.