Thanks for the replies, Goldenearthgirl and Honey.
I didn't think I used too much pigment, but it sounds like maybe I did.
I'll try less next time. I guess a dab'll really do ya. It's scared me off a bit, though -- I was going to use the same red oxide powder in another loaf soap. Hate to make another loaf just to have the same problem. Maybe I'll go another route and experiment later. The brick red oxide gave me that deep red, though, that I can never seem to get with the non-bleeding red liquid. I guess red glitter will help in the meantime.
I was originally planning to sell this soap at a craft fair, but I don't know if I should now. I will probably call this a learning experience and use it in my own shower. I'd hate for anyone to be unpleasantly surprised, even if it does rinse out. I hesitate to sell anything I don't feel 100% good about.
Sigh.