Frisk headed out. The sun was bright; and they shielded their eyes as they stepped into it, leaving the front door open to let the fresh air permeate the house... and hopefully hurry Toriel into joining them.
The official celebrations, which Frisk had helped Asgore and Toriel plan and prepare for, wasn't until tonight; they would celebrate the sundown, and likely well into the night. But nobody intended to wait until the sun neared the horizon to be happy together. Muffet had a stand, providing refreshments- although they decided to avoid eating any of her pastries, given that they felt their ingredients often should remain a mystery.
Frisk was noticed first by a small, furred monster; elderly and looking somewhat like a rabbit, he hobbled up to them.

"Ah, Frisk, Frisk m'dear, there you are, there you are, you know, people have been wondering when you would appear, yes, this is all because of you my dear. Mm, hmm."
"Ah- thank you." Frisk smiled politely. They had no idea who they were talking to. "Are you having a good time?"
"A good time, oh dear me, oh yes, the sun, it's very nice on the fur, isn't it, not that you would know I suppose, since you have no fur of course, but it is, very pleasant, very warming, and of course- everyone is so happy- yes, it's a good day, a good day."
Frisk was barely able to politely excuse themself as another monster came up, wanting to say hello, to thank them, to get a few moments of their time; and then another, and another. Many of them were near strangers to Frisk- they hadn't seen so many monsters together since that first celebration, a year ago. It was overwhelming.

They were trying to find a way to get away from the crowd, and were starting to worry about being polite less and less, when a shout cut through the chatter.
"There you are, ya punk!"
The monsters parted before Undyne and she bore down on Frisk; scooping them up into a rib-cracking hug. They squeaked in protest, squirming; but when she put them down, they were grinning. The other monsters all backed off out of respect for Undyne. Sometimes Frisk wished that was the sort of respect they got- more awe, and less easy familiarity and eagerness to be close to. It would be nice to have less of a mob around them.
"Hey, Undyne, Alphys." The smaller monster had been clinging to Undyne's belt; she looked even less thrilled with the crowds than Frisk was.
"You're, um, getting a lot of attention, Frisk," she pointed out, looking around and adjusting her dress. Frisk suspected Undyne had picked it for her; it was set in beautiful autumnal tones, which complimented her yellow skin.
"I noticed," they said; glancing around to see if anyone was likely to overhear, they followed it up with, "it's overwhelming, actually."
"Don't worry, Frisk, I'll beat off anyone who bothers you!" Undyne stood tall; she had dressed up too somewhat, wearing knee-high boots over black trousers and a waistcoat.
"Thanks, Undyne."
"Well... Maybe I won't beat them..." Undyne mused. Frisk grinned.
"Thanks, Undyne..."

The couple wandered around, with Frisk following them. They felt like a bit of a third wheel, with Alphys leaning close to Undyne and them talking mostly to each other; but every few steps someone called their name or waved to them, and for now they were happy to enjoy the celebrations like this. Feeling a small step removed from them, rather than dropped in the middle.
Of course, not every monster was going to be put off by Undyne's presence. She had to hint to a couple of monsters to back off- and hinting wasn't her strong point. Napstablook also came over to say hi- although they left quickly, despite both Undyne and Frisk telling them they didn't have to. Finally, a familiar voice called to them over the chatter, and Frisk turned to see Papyrus coming towards them, followed by Sans.

They all greeted each other enthusiastically- although it was clear, as he rubbed the top of his skull, that Papyrus wished Undyne was a little less enthusiastic- and they started to wander around again. They were a group now, and Frisk was somewhat tucked in the middle. They still got called to, though.
"You alright, kid?" Sans always noticed. They could lie, of course, but he would know. They shrugged.
"I'm okay, just, you know..."
"Not great with crowds." Frisk grimaced at him.
"Why did you ask if you knew the answer?" He shrugged, not saying anything.
They all stopped to talk to Asgore. Frisk gave him a big hug- his weren't as painful as Undyne's, or as pointy as Papyrus'. He was quietly happy, and for a little while they all stood together- but his approachable demeanour resulted in more people coming to talk to Frisk, and they ended up slipping away into his house, leaving everyone behind.

They had a bedroom here; large and airy, the wide window let in plenty of light, good for painting. Perhaps that was what they should do. They placed a heavy sheet of white card on their easel, and pulled on an old shirt and an apron to protect their clothes.
They couldn't really celebrate with the rest of the monsters; they thought they had wanted to, but really, they just wanted to celebrate with their parents and their closest friends. The crowds set them on edge. They were getting better about it- and monsters never made them as nervous as other humans- but it was still enough to rob some of their pleasure in the day.

They would find their own, though. They squeezed paints of different colours onto a palette and glanced out the window. Even if they had had the ability and patience, they didn't have the time to accurately capture the scene below; but they could do something more abstract. A gathering of varied lights dancing in the trees. They started to lay out colour; not worrying too much about the end result, just enjoying the swirl of the brush and the blending of colours.
So caught up in their creative flow, the didn't notice they had company until they stood back to examine their work and see what to do next. Then their father's deep voice made them jump.

"It's a beautiful day. It's a shame for you to stay inside."
They flushed; putting down the palette and brush, they turned to him. "Um... I know. I just-"
"Don't like crowds?" Frisk frowned at Asgore. For a moment they wondered if Sans had said something; but that wouldn't be like him at all. It was more likely that Asgore had put the clues together. They hadn't done a good job of hiding them.
He sighed into the silence and came over. "I did wonder if this would happen," he said, picking up one of Frisk's paint rags and taking their hands. He wiped their fingers as he spoke. "I should have kept a closer eye on you."
"It's okay. I didn't have an anxiety attack, I kept control over it." Frisk smiled at him; he caught their eye and smiled back.
"Well, if you're up for it, I had planned to show you- I set up a table, for you and your friends, away from the other tables. And I made your favourite bean burgers- we can see how well they barbecue."

"You did?!" This got the reaction Asgore hoped for; Frisk smiled wider, eager. "Did you also-"
"Yes," he grinned, "I also got you some corn on the cob, that can go on as well. And we have tomatoes and mushrooms to put on."
Frisk moved to hug him; but stopped, looking at their apron. He helped undo it and pulled it over their head.
"You should wash," he said, "before you get more paint all over yourself." He steered Frisk to the bathroom, where they saw he was right- somehow, despite their best efforts, they had a blob of blue on their nose, and a long smear of orange across one cheek. They took care washing their hands, trying not to scratch off the silver nail polish they had painted on, before scrubbing their face.

When they joined their friends, they were pink-cheeked but clean. Toriel had joined them; she gave Frisk a hug, and they thought it was likely Asgore had mentioned where they had gone to her. She was sat at an opposite corner of the large picnic table to her ex-husband; Sans has saved Frisk the corner across from her.
There were a few of these tables dotted around; the monsters with fire magic were the only ones Asgore had wanted cooking food on open fires, but there were dishes laid out and huge barbecues and cooking pits were starting to fill the air with a smoky smell. Many people had contributed- although a lot of the food was being saved for the evening celebrations, there was plenty here, for everyone to share. Asgore had stacked the food he'd prepared on a table near theirs, with a barbecue nearby. Frisk noted a large bowl of spaghetti nestled in with their salads and burgers- and a few of Sans' hot dogs. At least Papyrus had rapidly improved with access to human cooking books, shows, and Frisk and Toriel helping, but old habits died hard and Frisk suspected it would only be eaten by unsuspecting monsters with no idea who made it.

Once Mettaton arrived, Frisk didn't get any more unwanted attention; he had become even more of a celebrity, at least as far as the monsters were concerned. Purely being a monster celebrity had given him some quick recognition on the internet; but he was finding that becoming a star amongst humans was quite different to being one in the monster community.
His love of attention and "spending time with the audience" took a lot of pressure off Frisk and they relaxed; enjoying the sun, the food, the positivity; the chatter of their friends, of Undyne winding up Papyrus and Sans dropping the occasional gag between his platefuls of food. Frisk, instead of getting up to get their own, picked at the food he was helping himself to- the reason they gave was that it made his portions and frequent trips for more look more justifiable, but the reality was that they just didn't want to get up. If they stayed as they were, they wouldn't miss anything and nothing had to change.

Asgore got up to start cooking food on the barbecue; Sans continued to get enough to share, although Frisk noted that he was eating less, and getting their favourite foods more. He was also quite quiet, and what he did say seemed to be jokes designed to divert attention from himself- usually by getting a reaction from his brother.
During one particularly loud back-and-forth across the table between Papyrus and Undyne, Frisk nudged him. "Are you okay?"
There was a pause before he replied. "Just enjoying everyone being happy."
"Are you happy?"

"Yeah kid, I am. Are you?"

Frisk beamed, and nodded. They were.

It didn't escape their notice, however, that as the afternoon wore on and the sun started to lower, that he was slowly being less and less outgoing- and less convincing when he said he was okay, pulling out jokes and pranks to distract the others. Frisk wasn't fooled; but they were too distracted by the celebrations to dig into the reasons why, a fact that Sans used to divert their attention more than once. As the sun started to touch the horizon, and a hush fell over the monsters gathered near the entrance to the Underground, they realised he was nowhere to be seen.

If Sans didn't want to be found, he wouldn't be. For all Frisk knew, he could have gone back into the Underground, or he could have headed further down the mountain, where they had built shops and hotels to accommodate humans and monsters together; he could have gone somewhere else entirely, for all Frisk knew. Still, they had to try. They slipped away, sending a text to both Toriel and Asgore once they were gone, saying they needed a little space and would be back soon, and not to worry.
They managed to reach the entrance to the mountain without being stopped by anyone. He wasn't there. They headed in to where the barrier had been; then beyond, to where they had woken after it had been broken. They continued on, past the throne room, to the long, golden corridor, where dying sunlight forged pillars; the corridor where Sans had "judged" Frisk for their actions, and spoke of their determination to do the right thing.
He wasn't there either.

Frisk returned to the surface. They couldn't wander the entire Underground to try to find him, even if they thought it was likely they would find him. They pulled out their phone. One last attempt. In hindsight perhaps it should have been their first.
As the phone started to ring in their ear, they heard a jingle from nearby. They spun around, trying to see where in the trees it was coming from, when a light caught their eye. They hung up as they made out Sans, leaning against a tree, holding up his phone as if it were a beacon.
They sat next to him as he tucked his phone back into his pocket.
"Remember sittin' here last year, Frisk?" Frisk looked around and realised- this was the tree they had leaned against, talking, or just sitting in comfortable silence with him until they had fallen asleep. They gave him a concerned smile.
"I hope you're not going to fall asleep this time. I don't think I could manage to carry you home."
"Nah. Just thinkin', kid."
"What about?"
"D'you remember the first night we were out here? What we talked about?" Frisk nodded. "You still worry about losing all this?"
Frisk bit their lip. "Sometimes, I guess? But... not as often, any more. I'm doing better. What about you?"
"Sometimes," Sans repeated. "You can't know what it was like, kid. To know that, no matter what we did, one day... We'd lose it all, no warning, no memories. Just reset. Thought you were behind it, for a while."
"Is that why, uh... if you hadn't promised Toriel..."
"You remember that, huh?" Sans shrugged. "Part of it, yeah. Point is, sometimes it's hard to believe this isn't going to disappear."
"Sans..."
"I'm okay, kid." He grinned at Frisk. "Just... thinking. You should go back."
"No." They hunched down against the tree. "I'm not leaving you alone."
He sighed. They sat there together, the chatter of celebration more distant than last year; but more real. Frisk did belong. This was real. They just wished they could help their closest friend feel the same- but he, along with Toriel and Asgore, had told Frisk that same sentiment before. They knew that there were times it didn't help. They hated feeling like there was nothing they could say or do, so they just leaned against him, reminding him that they were there. No matter what he expected to happen, they could remind him that right now, he wasn't alone.

After a while, he shifted. "Okay, kid. Come on. Let's go celebrate."
"Are you feeling better?" Frisk sat up and turned to look at him.
"I told you- I'm okay. Just thinkin'." They pouted at him. "But yeah, I'm feeling better," he relented. They beamed and jumped to their feet.
They trudged through the trees together; not saying anything. He didn't suggest a "short cut", so it was a few minutes before they rejoined their friends, letting the quiet between them only be interrupted by the chatter from the monsters around them. Toriel didn't say anything when they rejoined their group- although her look made Frisk suspect that she would have words for them later- and Asgore simply squeezed their shoulder, clearly concerned but knowing they wouldn't want a fuss.

Their friends, though, had no such restraint. Papyrus' loud concern for his human friend was coloured only by his frustration that Sans was even slacking off from celebrating; Undyne grabbed Frisk, completely messing up their hair before they squirmed free. They pouted and let it down, before jabbing her in the side. Alphys watched, amused, until Undyne decided to lift her shrieking onto her shoulders.
Frisk caught Sans' eyes. He was a master at hiding his expressions, but they were getting pretty good at seeing through him and they thought that he was happy. They beamed at him, and he winked back. The people they cared about most in the world were all here, and all happy, and all celebrating.

For this moment, what more could they ask for?