Charm kiting Umbrous Toilers in Maiden's eye is pretty good exp. I usually pull 3 or 4 at a time, charm 1 and have the rest beat it down, usually when charm breaks its at half health. Charm another, have it attack the one that didnt get charmed last time, and chant the one you charmed until its dead. charm should break about this time, recharm the one you just charmed and have it attack the others. To keep it the others from killing your pet so you dont get exp, make sure you have inviz up and use inviz when your pet gets to about 5% to break charm.
On a full mana bar I can do this for about 3 hours, and i really dont have any major mana or int items to boost my mana. If you mix charm kiting with chant kiting you're mana will last a good while.