At first they called themselves Guinea and Pig -- she was Guinea, and he was Pig -- because that was what they were: guinea pigs for the higher power in the space ship. They didn't want their real names used because they were in the process of getting rid of their identity. Later they called themselves Bo and Peep, apparently because they considered themselves to be shepherds. Their followers became known as Bo Peepers.
This woman had written a diary about her experiences while she was in the cult. My informant, as I call her, told me that she had found out the names of the real names of the leaders of this cult were Marshall Herb Applewhite, and the woman's name was Binder Truce Dell Nettles.
And from another site:
Do and Ti (aka Bo and Peep)
Birth/Death:
Do (1931-1997) was born Marshall Herff Applewhite in Spur, Texas;Ti (1927- 1985) was born Bonnie Lu Nettles, birthplace unknown.