8531
Sejanus meanwhile secretly plots with Livilla to usurp the monarchy for himself by poisoning Castor and systematically eliminating any ally of Agrippina and her sons .
 person: Sejanus; person: Livilla; person: Castor; person: Agrippina
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 person: Sejanus; person: Livilla; person: Castor; person: Agrippina