She is living the good life 
Looks like he is done and definitely needs a break 
Has this been in bug reports yet, what makes them wear a hat?
@JoyIsFunner and what makes them wear only the underwear apart from the hat in the first place 
?
But you’re right. Have not seen this reported. Maybe I should log a bug for this. Seems very strange behavior: underwear and hats 
@EllaEstella It’s because they can’t re-enter the business after closing hours even though your zoi was still there.
The terrace is a death trap.
I intentionally built a death trap house. Well, to be fair, I didn’t realize it was a death trap house at first. I managed to get a fence to close all but one square. During parties, zois would go outside in the backyard, and they couldn’t leave after the party.
First, I felt bad and helped them with the doors. Then there was something that happened which I caught on video (it’s in my YouTube channel trailer starting at 0:16 and goes until 0:30) that made the zoi’s father come outside and introduce himself. He discussed something about moral dillemmas, talked logically, had a debate, and discussed the cause rising crime rates. Then my zoi was like, “How would you like to be the only guest at my new house party. Don’t worry that you haven’t eaten, we have lots of food.” Old man watched through the window as the family ate meals he wished he could have. I don’t know if the cold got him or the starvation. But I took care of that problem. 
Not the death trap! That wasn’t the problem.
You might want to eliminate that death trap at your business though.
@EllaEstella It’s NPCs dressing that way in your game. Definitely a bug report needed unless they might’ve had mod outfits on or something.
Was it a brand new game or a pre-existing one?
In several of my pre-existing ones, zois were not changing into the right clothing all the time, and especially if they had a queued action (even if autonomous) following an action where a wardrobe change is expected in between. Such as the zoi wakes up and goes downstairs to help themselves to leftovers from the fridge. There was more than enough time for the wardrobe change, but this was during the version0.7 and the zoi put the food on the table, took a piece and started eating in his sleepwear. It happens when they should change out of fitness or other outfits as well. And zois will wear their robes for a long time if they have tasks queued up after a shower.
I wonder if it happens to everyone?
It’s happened in all my games from prior to the update, so I used style yourself on all to reset their outfits. I hope it fixes it. (I have no new save games created after the 0.8 update.)
Of course that’s not possible with the NPCs. Considering that most NPCs don’t live in the city, and I don’t think they all even have a permanent existence (being able to appear multiple times without forming relationships with residents). But regardless, seeing this shot made me wonder if there’s a spa nearby. It might be another one of those situations where the business closed, so zois left without the usual automatic outfit change because of whatever causes this failed outfit change.
The your zoi has gone on an astral travel. 
@Starwing Oh my… A death trap… sounds like sims
I know, you don’t want the NPC Zois to die in your shop but in Inzoi it works differently than in Sims. In Sims you would already have the whole shop full with urns or tombstones as the Sim would die right after their hunger is at 0. In Inzoi they can still go for at least half a day after that. It looks like they would die soon when you watch their behavior but so far everybody has surrived the night 
Nevertheless it is a consideration to get rid of the trap
@Starwing Yes, I will report a bug on this.
I do not have any mods in my game, so this cannot be the reason. All of these Zois were NPCs. And there is also no Spa near to where I saw the Zois.
Regarding the outfit change: I haven’t noticed this in my game. The only thing I have as well is that they use to still wear their fitness outfit for a couple of minutes after doing fitness before they automatically change to everyday again. Same after shower with the bathrobe. But it is never for long, always a couple of minutes.
My save file is from before the March update, so old save file. But I did never see that before. It started happening after the latest v.0.8.0 update in April.
What I find especially strange that every NPC Zoi I saw so far in underwear was always wearing a hat 
You’re right, it took a long time for me to get rid of that unwanted leftover party guest. (It’s not something I usually do! I had to test it out too. It was when the game was very new still.)
There’s a good chance they can survive your terrace, and thankfully, they don’t leave silly tombstones when they pass. They just kindly go away and leave an urn at the funeral home. I love how polite zois are that way. 
Seriously though, I truly love inZOI more than any Sims game. There are a lot of things from TS2 that I’m nostalgic about and some features I’d love to see in inZOI, but I’m generally so much happier being an inZOI girlie. (Apologies for going off topic there.)
As long as there are no autonomy bugs for NPCs, then your terrace is probably just fine. 
If you really want to, you can leave a 2 square gap. That’s all they need. Even if you put a tree there, they can get out safely.
But it’s only a concern if there’s another bug where NPCs don’t take care of their needs. I had a lot of issues with that once. I used to have to go around all the houses and set everyone’s hunger to full at the end of the day.
@EllaEstella the hat must be so the bug is extra fun! There’s something about hats though. Some NPCs never take them off. The zois who sang carols during the winter festival (in the December update) still wear their Santa hats around my cities.
This is probably a way for the game to create different “everyday clothing” styles for NPCs. The game automatically assumes that an outfit that includes a hat cannot be a “sleepwear outfit”. And as for why the lower part of the clothing turned out so strange - how would the algorithm know about that if there’s no explicit prohibition for it in the code 
In that case, the logic makes sense - there are others in hats too, but they have the rest of their clothing matched more successfully, so they don’t stand out