A/N: This is my first Hey Arnold! fic and my first fanfiction in... well, over ten years. I wanted to post it on Christmas, but things happen.
Arnold isn't content with the mystery left lingering over his head. Miracles, a Christmas angel, it doesn't make sense.
It's easier than he expects to get Gerald's attention focused on the antics of the boarders and slip out to the hall. He rushes to the door, throwing it open, but no one is outside. Still, there are two sets of footprints in the snow leading to the boarding house - someone led Mai here. His eyes follow the retreating footprints up the street and he nearly topples down the steps at the lone figure he spots. He would know those pigtails and that pink bow anywhere.
He grabs his coat, slamming the door shut as he runs down the stairs. "Helga!" He calls out, running after her. She stops for a moment and then breaks into a run herself. She darts around a corner and when he reaches it she's nowhere to be seen.
For a moment, he's lost. Where did she go? Why did she run? Yet even where his footprints have mixed with hers he can see where one set turns toward the alley. Calling her name softer, he steps into the alley.
Helga hops up from where she had crouched behind a trash can and fixes him with one of her best scowls. "What do you want, football-head?"
"Why did you run?" is the first thing he spits out, not wanting her to run while he thinks of what to say. He's not put off by her scowling and harsh demeanor, of course. Even on Christmas he would expect nothing less from her.
"Because I didn't want to deal with you, doi!" Helga shoves him aside, stomping back out onto the street. It's then he notices her socks. She doesn't have any shoes on.
Arnold grabs Helga by the arm before she can take off again. "My Christmas angel," he says to himself, awe in his voice. Helga hears him, though, and her heart races at the thought of being called an angel by him. Warmth floods through her and for a moment there's nothing but her and Arnold, his hand on her as he calls her his angel. She starts to swoon - a window opens above them and she smacks her cheek, snapping herself out of it.
"Watch the goods, bucko!" She pulls away and turns to face him. "What do you even want?"
Arnold is looking at her in a way that she can't decipher. He looks happy? hopeful? thankful? surprised? The look is gentle and sweet and directed at her, tearing at her defenses.
"Come on, football-head, what - what is it?" She presses, voice strained as her nerves fray. What is he thinking? Could he finally be realizing the truth behind all her bullying and blustering, the secret kindness in her heart that he seems to bring out, how she will go to any length to see a smile on the face of her football-headed idol of passion?
Helga doesn't want her act of kindness acknowledged, Arnold realizes from her tone. It's how she always brushes things off when she surprises someone with anything other than her usual brusqueness. He tries to think of why she would do it if not for thanks, why she would help in the first place. She has nothing to gain from it.
He's buzzing with questions, but holds his tongue. "Let me get you a pair of boots to wear home. You shouldn't be wandering around in just socks." He takes her hand before she can argue and pulls her back towards the boarding house. She silently lets him lead her back.
At his house, Helga demands to stay on the stoop and that Arnold tell no one that she was ever there. He agrees and almost laughs, because of course no one can know, that's the Helga Pataki way.
A quick search in the hall closet turns up an old pair of his grandma's snow boots, a little worn but not too bad. Helga accepts them with an "I guess these will do" and then shoves her feet in them. They're slightly big but better than before. She turns to leave without even a goodbye.
This time they both nearly fall when Arnold steps out and grabs her in a hug. "Thank you, Helga," he whispers, hugging her tight. "I'll never forget this."
Helga freezes for a moment, confused and then delighted and then distressed, pushing him down onto the snow-covered steps.
"Hey!" she snaps, voice low out of awareness of the people inside. "I was never here, and this never happened, okay? Speak of it again and I'll make sure you never speak again!" She waves a mittened fist at him before bounding down the steps and back up the street.
"What are you doing out here, man?" Gerald asks as Arnold is standing and dusting himself off. "I turned around and you were gone and that Ernie guy would not stop talking about some building."
"Sorry, Gerald, I thought I saw someone," he answers, trying to play it cool but he can't help smiling despite the rough treatment. As heartwarming as Helga's actions were, there's comfort in their usual relationship. "I just slipped when I came back up the stairs."
Gerald shakes his head in disbelief as they return to the festivities inside.
Helga runs until she knows she's out of sight of the house before she spins in the too-big boots, hands clutched over her chest. She lets out a delighted squeal. He thanked her! He thanked her and was worried about her! He noticed her! More than any year before, she can truly say it's been a merry Christmas.