Essentially, their roles are more like those of Queen Beryl's commanders rather than the Negamoon Sisters, as each of them has her turn to go on several missions in a row, rather than taking it in turns to carry out their master's bidding.
Eugeal first appeared in Episode 13, Birthday Blues (2), to inform Doctor Tomoe of Kaorinite's death. The others first appearaed in Episode 14, Hello, Sailor Mini Moon. All of them were shadowed, until just before Eugeal's defeat, in which Mimet was seen clearly for the first time.
Eugeal and Mimet were both sending Daimons to extract Pure Hearts. Eugeal was searching for the three Pure Hearts to get the Purity Chalice, and by the time Mimet was up, the Purity Chalice was already awakened, and the reason Mimet was looking for Pure Hearts was to feed them to Mistress 9.
The Witches 5 spend most of their time in a room behind a door that says "Witches 5" on it. After Mimet put acid snails in Eugeal's car, corroding the brakes and causing her to crash over a cliff, a poster was stuck up on the door, altering it to say "Witches 4". Later, Mimet entered Eugeal's power device, but Telulu pulled the plug on her as revenge for stealing her job. After this, another poster was put up on the door (and quite badly) to make it say "Witches 3".
Following the death of Mimet, as the series was reaching its end, the remaining three witches each only lasted one mission. Telulu's plan revolved around using plants to extract Pure Hearts, but was killed when a giant plant monster of her creation turned on her and selfdestructed. Byruit's plan was to use computers controlled by her nanocuff to take Pure Hearts from people, but when her nanocuff was damaged, it backfired on her and dissolved her. Cyprin and Petirol, with whom she shared her mind and body, used a glass statue to extract more Pure Hearts, but Sailor Jupiter and Sailor Mars tricked them into destroying each other.