Klukai

HK416 (also known as HKM4, Clukay or Klukai) is a serious and foul-mouthed Doll who takes great pride in her status as an Elite T-Doll and her combat performances. She also holds a strong sense of justice that pushes her to protect the weak and her teammates. Paradoxically, as pointed out by AK-74U, 416 considers that only excellence in tactical and strategic thinking and knowing how to protect their own lives will differentiate T-Dolls from mere tools to be used by humans, but she also puts great value in sacrifice in battle and following orders. She also commented on not being particularly fond of fighting and being somewhat risk-averse, but having no choice on the matter within Squad 404.

Within 404, HK416 acts as the main fighter, possessing the best combat specs. She begrudgingly respects SMG UMP45's authority despite their shared past, but often complains about 45'reckless strategies. 45 often mocks 416's pride but respects her skills, considering her for next in line as squad leader. 416 is also, by choice, AR G11's guardian, but frequently gets angry at her laziness and warns her that she won't always be there to take care of her. She has sat out multiple operations while in 404, waiving her part of the payment, and frequently reminded her teammates that she planned to leave the squad sooner rather than later. Despite 416's complaints with 404, she had similar claims about Griffin Dolls, judging them to be too unprofessional and hard to work with.

Because AR M16A1 caused her to be expelled from Griffin, HK416 holds a deep grudge against AR Team as a whole and aimed to beat M16A1 in a fight to prove her superiority. She is also jealous of the comfort the AR Team enjoys as a Griffin team compared to 404's harsher life conditions, and criticizes the AR Team's supposed hero complex. M16A1 herself does not care for 416's revenge, saying she was fond of her before having to expel her from Operation Butterfly, but thought nothing of her after she joined 404, seeing her desire for vengeance as a sign of insecurity. After temporarily returning to Griffin during the Continuum Turbulence event, 416's thirst for vengeance has softened as she has given more thoughts to her present and future rather than worrying about living up to others' expectations of an elite T-Doll in an attempt to heal her wounded ego.

HK416 sometimes uses German expletives, like “dummkopf” (“stupid”, often directed at G11) or “Arschloch” (“asshole”, directed at M16A1). Before the Butterfly Incident, HK416 was known as HKM4, a reference to the name of her rifle before the Colt lawsuit. Her sister model is RF G28, which is a designation of the HK417 (or HK241), a DMR variant of the HK416 chambered for 7.62x51mm NATO and used by the Bundeswehr. While G28 openly loved her big sister, 416 was much more reserved, bothered by the notion of a Doll being tied to a family.

The Dorm Furniture Convenience Store - Liquor Cabinet states, "DO NOT Sell Liquor To HK416," which may indicate that she has a low tolerance to alcohol, but given that she was able to keep up with RF Mosin-Nagant in a drinking contest, she might merely have a tendency to overdrink. As Clukay, she revealed her complicated relationship with drinks: she found another connoisseur in Gin and talked about her liquor collection, but couldn't hide the fact that she is a bad drunk and therefore hesitates to actually indulge.

HK416 has long, light blue hair that is put up in a ponytail, neon green eyes, and a small red teardrop face marking under her left eye.

She wears a purple eyepatch bikini with multiple straps and a criss-cross halter. The bottom has a small frill and has flowers attached at the left side, in addition, she also has a transparent cropped jacket, which has neon green bands halfway on the upper arms on the sleeves. She has a thigh strap, which has a holster for a pistol, and also has a black choker with a heart on the front, as well as a dark blue visor cap. She has tinted blue-to-green gradient sunglasses, which she keeps on top of her head.