the previous poster's build is ok. i would suggest moving the 2 from imp healthstones to health funnel (your FG will need the heals) and move the point from demonic resilience into mana-feed (he ooms quick).
where the rest of your points go depends on what you're doing. as this is a pvp thread you're going to want instant corruption. if you were to do PVE with your FG you'd want to fill up destro and leave aff alone.