My biggest headcanon is that Nil came up with a nickname for Aloy since he literally did not know her name until right before the Battle of HADES. So… 

“Have you found a new partner yet?” Aloy asked.

Nil finally turned to look at her, one eyebrow raised quizzically. “I thought we were partners.”

Aloy recoiled slightly with surprise. “Uh… I have my own roads to follow, Nil.”

“And they seem to lead back to bandits,” he replied reasonably. “That works for me. I’m not suggesting a Carja wedding.” Aloy’s cheeks warmed at the mention of a wedding, much to her annoyance.

Nil nudged her shoulder slightly with his own. “I’m never lonely when there’s killing to be done.”

Like I was worried about you, she thought acidly, but declined to comment. Perhaps it was best to let him think they were a partnership; maybe it would keep his viciousness on a leash if he knew she would be keeping tabs on his activities. She gave a reluctant nod, then rose to her feet, brushing dust and grass from her legs. “Time to move on,” she told him. “And… thank you. For the meal.”

He nodded, but made no move to rise. “A brief encounter for us, but the end for them,” he said, with a nod of his head towards the camp. “They were squalid lives anyway. Until next time, Suntress.”

Aloy gave him a funny look as she readjusted her weapons on her shoulders. “Sorry? Did you say ‘huntress’?” She wasn’t sure if she had misheard him; everyone in the westlands had been addressing her as huntress.

But Nil shook his head. “Suntress. You know, tresses of hair scalded crimson like the fiery sun… though it also rhymes with huntress, which you undoubtedly are.” He grinned at her. “Such a satisfying name, don’t you think?”

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“Did bandits wrong you somehow?” Aloy asked. Maybe there was a good reason he hated them so much.

“They wrong us all,” Nil replied briskly. “They live filthy lives, so they have to die that way too.”

Aloy breathed a tiny sigh of relief. Well, that’s more normal, she thought. “So you hunt them down to help others?”

Nil frowned at her suddenly. “No, no. For sport,” he corrected, as though this was obvious. “I can’t wait for wars anymore. Life’s too short, and the thrill of death too sharp. If you kill a tribesman, there’ll be retribution. Hunt a boar, and they’ll complain if you waste the meat.

“But bandits?” He smiled slowly, and his face reminded Aloy of a thirsty man enjoying the first sip of honey mead. “They’re vicious; they always put up a fight; and no one cares if you kill them!” He nodded at her brightly, clearly under the impression that she would be impressed with his reasoning.

But Aloy was not impressed. What if one day, his fingers ‘itched for the bowstring’, as he had said earlier, and there was no bandit around to take the hit?

“I’m not sure who’s worse: you or them,” she scolded.

Nil smirked at her and tilted his head charmingly. “We’re standing, they’re not,” he explained. “Clearly we were better.”

“Why limit yourself to bandits, if you love killing so much?” Aloy knew her voice was hard and disparaging, but she couldn’t help it.

“Janeva suggested it,” Nil replied, to Aloy’s surprise. “She said it was the only way for me to stay out of prison. She spent a lot of time talking to me while I was there. It was… strange.” Nil frowned pensively. “She once said I couldn’t see the difference between black or white, that all I saw was red. It’s hard to know what she meant, but it felt right at the time.”

Nil’s eerie silver eyes traced over Aloy’s face, and he reached forward and gently took hold of a strand of her flame-red hair, running it through his fingers before flicking it over her shoulder. “It feels even more true now.”

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Aloy sighed and looked down at the bodies scattered around the strangely-dressed man. “Varl told me there would be bandit ambushes on the road,” she muttered, mostly to herself.

The man replied, his voice sounding oddly apologetic. “Well, it’s not all good news. They don’t always come to you. Most dig out a camp, and there they’ll sit like spoil on meat.”

Aloy glanced at him sharply, one eyebrow unconsciously raised in puzzlement. Why would bandits attacking ever be good news? And why does he talk like that? Like he’s coming up with poetry on the fly?

Then she caught his expression. His eyebrows were raised expectantly as he watched her. Oh. He wants something from me, she thought with a touch of resignation. It seemed that everyone she met along the road needed something from her. “Unless… someone does something about it?” she guessed.

The man smiled again, and this time the expression lit his face with warmth. A strange, irrelevant thought entered Aloy’s mind: He’s handsome. She wasn’t sure why she hadn’t noticed it the first time she looked at him. More importantly, she wasn’t sure why she even noticed it at all.

“I like you,” the man said, and his voice was tinged with approval. “Follow the trail of smoke on the other side of the ruins. I’ll be there.”

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The whisper of shaft against leather as she pulls the arrow from its quiver. 

The gentle creak of the bowstring as she pulls it taut. 

A narrowing of her eyes as she hones in on her target, a slight hint of a smirk as she catches it in her sights. 

Then a careful release, and the arrow hits home. 

Nil watches her hungrily, his heart pounding as he thrills in the death she brings. She might deny it, but he knows she loves the hunt.

Rost’s face was as stern as ever, but for the first time, Aloy could see a hint of distress in the line between his eyebrows. “For your sake, I must go where you will never find me. This… this is goodbye.”

Aloy swallowed the lump in her throat and glared at him. “No. No, it’s not. You taught me how to track. Wherever you go, I can follow.”

Rost shook his head gently and began to walk away. “Not this time.”

“This time, and every time,” Aloy insisted. She jogged after him and held up the precious charm in her hand, the charm Rost had just given her. “I’ll be wearing this when I find you.”