The word Eve is used to describe the drug 3,4-methylenedioxyethamphetamine (MDE). It is a close relative of MDMA (3,4-methylenedioxymethamphetamine or "Adam
"). These two compounds are common in ecstasy pills and it is quite common that an ecstasy pill may be cut with both of these chemicals.
Both chemicals have very similar effects, however Eve provides a greater "loved up" feeling and a larger sense of "connectiveness" between people; Hence the nickname "The Love Drug".