|Full name||Kain Schwaben|
|Affiliation||East Germany State Security Service|
|Voice actor||Fukuyama Jun|
|Released on||CN, TW, KR, JP, EN|
At first K acted as a middle man, who trades information between factions that are friendly and hostile to Griffin & Kryuger. Throughout the story interactions it is clear that K is also a cautious, resourceful and skilled person. K had evaded many attempts at tracking him down via means of illegal modifications on his servant dolls, leaving escape passage ways at various locations and hidden weapon stashes as back up plans.
K's affiliation and background are revealed during the story event Polarized Light. K is the initial of his given name, Kain Schwaben (凯恩·施瓦本). K serves as Lieutenant Colonel of the State Security Service of Deutsch Democratic Republic (德意志民主共和国 国家安全部). His personality is stoic, rational and enigmatic. Very little information is known nor given by K regarding his background, his affiliation and stance up until Polarized Light. Though it was clear he worked with agent Angelia of the Bureau of State Security on many occasions, likely for common purposes.
- K's appearance in the collaboration event Valhalla is a very out-of-character cameo appearance.
- K's first appearance on the EN/JP servers was through the Valhalla event.
- Ingame files call him "Jason"