the difference between manga and .anime. is quit more evident here
in the manga Beryl very pretty and normal member of the moon kingdom but she is very jealous of Princess Serenity and the other scouts thus she becomes an easy target for the negavers. she finds the hide darkness in a basement room of the castle and with its power kills the 4 generals(the lovers of the inner senshi, Zoycite is really a male dont worry dic sucks and they changed it) and posses their body with negavers power to make them her generals she posses others bodies as well which causes Queen Serenity to send everyone to earth when she does it release all the people from Beryls power except for the generals cause they are all ready dead
in the end the negaverse gave her one last blast of power which could not stand up to the combined power of the 5 sailor scouts
one thing im not sure about (cant remmber) but will check into is if the negaverse its self is still around