Kayla Pieterse was a villainess from "Kicking the Bucket", case #39 of Criminal Case: Save the World, the 3rd season of the crime solving game Criminal Case (release date July 7, 2016). She was a member of the international terrorist organization known as SOMBRA, and was found dead near a well by the player and Jack Archer after being drowned to death.
The Bureau had been arriving in South Africa to prevent an assassination plan against Prince Abioye, and Kayla's posthumous reveal as a SOMBRA agent led the team to realize that Kayla had been Abioye's intended killer. It was revealed during the course of the investigation that Kayla attempted (unsuccessfully) to seduce Abioye's bodyguard, Willem Nieuwoudt, into giving her the Prince's itinerary.
As for her murder, Kayla's killer was revealed to be Kwanele Mthembu, Kayla's childhood friend and former lover. When Kwanele learned about Kayla's allegiance to SOMBRA, he insisted that he wanted to join the organization so he could inherit Kayla's newly given super intelligence. But when Kayla told Kwanele that he was too old to join SOMBRA, Kwanele decided to prove her wrong and impress SOMBRA by killing her, knocking her out and tying her up with yacht rope before drowning her in the well.