Iruka is not asleep when the window slides open, nor would his visitor expect him to be.
He does not know this man, but he has been waiting for him, ever since he lit the candles in his window that evening. Five burning wicks, scavenged from the corners of his apartment, and a message to the guardians who walk Konoha in the night. It's an invitation, an offer, and not one to be made lightly.
The man blows out the candles before he crosses the windowsill, a quick rush of breath that plunges the room into darkness. It's not up to Iruka what will happen -- he will not die, but he could be hurt. It's a risk, but there are good reasons for this custom to exist. Iruka believes that even the shinobi who have gone nearly feral can be pulled back from the brink, and he can't say precisely why he decided tonight to light the five candles in his window, but something about the moonlight had made him restless and brave and maybe a bit reckless.
"I might be going mad," his visitor says, his voice low and distant, threaded through with vague worry.
Iruka doesn't say anything, and just makes room on the bed next to him.
"I know what the others do," the man says. "Would you mind if I just--"
"You don't need my permission," Iruka says softly, trying to be as pliant and accepting as he knows how.
"Give it to me anyway," the man says. Iruka nods once, and in the dark, it's more likely that he feels the motion instead of seeing it, and then he wraps himself around Iruka, tucking Iruka's body against his.
His visitor is all sleek muscle and sinew, the sharp edges of ANBU armor uncomfortable where they press against Iruka, but he was prepared for a lot worse. He focuses on calm, steady breaths, and the man breathes with him, matching him, and they lie there quietly. Iruka still does not sleep, and neither does his companion.
Still, he wonders if he's helping at all. His voice sounds far too loud as he whispers, "If there was something you wanted--"
The clouds break then, and with the moonlight, Iruka can see the eyes behind his visitor's porcelain mask, one dark and one blood-red. "Just this," the man says. "Go to sleep."
Iruka obediently shuts his eyes then, and when he opens them, it's dawn. The space next to him on the bed is still warm, and the candles -- they're gone. They've been taken, and Iruka touches the melted wax left behind on his windowsill. He only has a memory of mismatched eyes, and it will be years before he knows the identity of his ANBU visitor that night.
Even so, he respects Kakashi's unspoken request that morning, and never lights the candles for another stranger again.