jackal (honkai impact)

Jackal, also known as Dr Cleo, is a honkai impact 3rd character. In chapter 21 she is alluded to be a former Schicksal valkyrie named Layla who had joined the organization to protect her sister but lost all hope when the latter died and eventually joined World Serpent. No longer believing in her former bright ideals, she became a cruel scientist who performs human experimentation in the name of defeating the Honkai.