I am replaying the Theives' guild questline, and I just finished the elven maiden, and I found Dar Jee and he told me his racist Khajiit joke (I am playing as a Khajiit) so for Roleplaying purposes, I got his Disposition down to zero, and he wouldn't talk to me, he kept running away when ever I came near him. When I ask to talk with him it says "Dar Jee is fleeing"

A big ol' charm spell should do the trick, then raise his disposition from there.

Thats what I thought. But what if I dont have a big ol' charm spell?

See Delphine Jend, she sells a fair few Charm spells.

But if you're on PC and not adverse to cheating, use the command moddisposition 0003599B