Nest Keepers

Nest Keepers are living hosts to bloodflies. The parasites lay eggs into their bodies and force them to protect the nests. Even without their limbs, the parasites will force the Nest Keepers to pursue intruders. Upon death, the hosts' corpses will release a swarm of bloodflies.

Appearance and Behavior
Nest Keepers have an unhealthy, mottled, grey tone and their skin has taken on a bumpy, leathery texture. A Nest Keeper's eyes are discolored, and their teeth are rotten and decayed. Their hair is missing, their nails are blackened, and they are dressed in the remnants of whatever clothing they had on when they were turned.

They fuss over the bloodfly hives, ensuring they are safe, and will aggressively attack those who are perceived as threats. If they receive significant damage, they will rip apart at the torso, releasing a fresh swarm of bloodflies.

Combat Tips

 * Nest Keepers are immune to most offensive gadgets, resulting in them being difficult to kill.
 * Firearms are relatively ineffectual against them; arm shots will dismember but not deter them, gut shots may release a swarm of bloodflies, and headshots are not guaranteed to kill them instantly.
 * Crossbow bolts will not instantly kill them upon a headshot, and even with the Hardened Bolts upgrade it takes several body shots to kill them.
 * Attempting to choke out a Nest Keeper with a few bloodflies nearby may kill him, releasing more bloodflies. They can, however, be safely choked unconscious without any bloodflies or enemies nearby.
 * Spring Razors require two releases to fully kill them.
 * Killing them with fire (such as incendiary bolts or throwing high-proof liquor) is the most effective method, as it instantly destroys both them and the bloodflies that surround them.
 * Sleep darts and stun mines work against them normally.
 * Stinging bolts do not work against Nest Keepers and they will continue unfazed.
 * Nest Keepers are vulnerable to assassinations from the back and drop assassinations.
 * Domino bypasses most of a Nest Keeper's resilience: Inflicting injuries on linked targets that kill them but normally wouldn't kill a Nest Keeper (e.g. a single spring razor release, dismembering body shot, or headshot) will kill the linked Nest Keeper as well.
 * It is still impossible to affect a Nest Keeper with stinging bolts this way.
 * Using Mesmerize on a Nest Keeper has no effect and the void spirit will be promptly despawned.

Searching

 * "Everything is alright. There. There." (to the agitated bloodflies)
 * "They need your blood. So I'll just draw it."
 * "It's alright my lovelies. I'll show her out." (if playing as Emily)
 * "You're a bad woman. I can tell." (if playing as Emily)
 * "You shouldn't have come here."
 * "Ahhh. And now I have to hurt you."
 * "They don't like you. Nothing I can do about it."
 * "Are you gone?"
 * "Why are you hiding?"
 * "I'll use your bloody guts to hatch new little babies."

When Bloodflies are Attacked

 * "You're upsetting them. Go away."

Being Attacked

 * "See my lovelies? They're all bad people. Just like I told you."
 * "Don't waste the blood... You don't know anything."
 * "Ung... Why... Why do you do that..."
 * "Yes, that's it, shoot me. Better me than them."

Trivia

 * Nest keepers could be argued as the Dishonored 2 equivalent to weepers from the first game. They've become infected by a vermin species and basically become a sort of "zombie" type enemy that is hostile towards the protagonist and most other NPCs.