bug Serial Killer Perk not working as described

[Kenpari]

Currently, the serial killer perk's description states that, when killing a human, a heart will always be harvested from them if they weren't hostile or didn't fight back. However, I've tested this many times with stealth kills, both from range and melee, and have never gotten a single heart from an instant kill on an unaware human. I've only tested it against hostiles, not innocent people, but according to the description, that should work as long as they don't fight back.