That's an original character.
The original of this image can be found here, since the original Pixiv upload was deleted: https://gelbooru.com/index.php?page=post&s=view&id=700754
Yeah, at this point it's pretty clear that image is not traceable to specific characters or a specific source. They look like original characters merely inspired by certain existing designs (I think of [url=https://www.animecharactersdatabase.com/characters.php?id=40548]Ayane[/url] and [url=https://www.animecharactersdatabase.com/characters.php?id=69809]Satoko Kusagakure[/url]) and if the original still exists it's certainly not findable for us.
Any further posts asking for this image would be redundant.
It's the OC/Persona of someone that goes by Skipos. They use it as their profile picture on multiple social media sites (for instance; Twitter/X:[url=https://x.com/skiposcmc]skiposcmc[/url])
[url=https://pbs.twimg.com/profile_images/2004950656826646528/jFUPzime_400x400.jpg]Link to Twitter icon[/url]
The Character is Makima from Chainsaw Man. This specific image is from chapter 74 of the manga.
[url=https://snipboard.io/pHeuzw.jpg]High-res ver.[/url]
That's Nako Sunao from Hitori Bocchi's OO Life.
The image comes from the anime. Here's a bigger res version: https://x.com/DailyNako/status/1175930113428377600
That's Fubuki, from One Punch Man.
That seems to be a slightly edited version of this picture - https://pinterest.com/pin/777222848195187860/
If you're logged in, you can right-click then open the image in a new tab: https://i.pinimg.com/1200x/62/72/00/6272004347aac0df48ba4f02f7973b6f.jpg
It's actually even better than the site's "download" option.
The comments on that upload say it's fan art by Siraha but I can't find anything like this under their name.
Absolutely AI generated. But for this one you have an original version available too! Even I am surprised.
Check it out. https://rule34.xyz/post/4076046