If you have Edwin in your party, as soon as you enter the Graveyard District he'll ask you to assist him to find the Nether Scroll in one of the tombs. This quest can be finished by killing the lich found in our Graveyard Lower Tombs 2 walkthrough. You won't actually get to see the scroll because once you kill the lich, Edwin will take the scroll immediately. You only get a line in your journal saying he intends to study it thoroughly.

After a couple of days (about 5 if I remember), the Nether Scroll will change him into a woman. After 20 days or so, there's an encounter where some guy is searching for Edwin... you can turn him out for some XP (they are not worth it) or cover for him. If you cover for him, he'll be back in 2 days and dispel the Nether Scroll effect and Edwin will kill him for witnessing the humiliation.