Short answers, pulled from the story.
The Lex Aquilia was a Roman plebiscite, enacted at some point in the 3rd century BC, that provided monetary compensation to property owners whose slaves, herd animals, or goods were wrongfully killed or damaged. It addressed a category of civil wrong called damnum iniuria datum, meaning damage unlawfully inflicted, and organized its protections into three chapters.
The exact date of the Lex Aquilia's enactment is disputed and no incontestable theory has been put forward. Three competing dates have attracted support: around 287-286 BC, linked to the Lex Hortensia; around 200 BC, as a response to post-Second Punic War inflation; and around 259 BC, linked to a consul named Aquillius.
Only Roman citizens could bring a claim under the Lex Aquilia. Among citizens, only the strict legal owner of the damaged property, called the dominus, had standing to sue. Those with lesser ownership interests were excluded, though an in factum action was available in some cases where the Lex Aquilia's direct requirements were not met.
The third chapter of the Lex Aquilia covered wrongful burning, breaking, or rending of property other than slaves and herd animals, using the Latin verbs urere, frangere, and rumpere. Compensation was based on the property's value within the thirty days nearest the damage. Jurists interpreted rumpere broadly as corrumpere, meaning to spoil, extending the chapter's reach to a very large number of additional damage types.
The second chapter of the Lex Aquilia fell out of use almost immediately after the law was enacted. It addressed fraudulent cancellation of debts by an adstipulator rather than physical property damage. By the 5th century AD the Institutes of Justinian at section I4.3.12 confirmed it was no longer in force, and the jurist Ulpian recorded its end in a single sentence preserved in the Digest of Justinian.
Corpori corpore is a Latin phrase meaning on the body of the victim by the body of the perpetrator. It described the direct causation requirement under the Lex Aquilia's first chapter: only someone who physically and directly inflicted the harm could be sued under the chapter's main provisions. Those who arranged for another to carry out the killing, or who caused harm only indirectly, were excluded, though they could face an in factum action.