Who is Lucius Domitius from Claudius the God and His Wife Messalina and what is their importance?

Lucius Domitius is Agrippinilla's son. After Agrippinilla and Claudius marry, Claudius adopts Lucius and names him joint-heir with his own son, Brittanicus. Lucius Domitius is later named Nero and becomes emperor before Claudius' death. In order to gain complete control, Agrippinilla poisons Claudius, enabling her son to reign in tyranny, even killing his own mother. Lucius is killed in 68 AD.