A while ago we had a thread about ukagaka. They are 2D desktop companions that was a part of the 2000s Japanese otaku culture, and never really made it to the west outside a niche circle. You can read the wikipedia page for more information on them.

While chatting with pez-san a few days ago, the topic of ukagaka was brought up. Originally I mentioned the idea of simulating a Heyuri-tan ukagaka on Heyuri, but I quickly noticed how much work that would entail. Then I decided on working on a web Ukagaka engine - there were some other similar projects in the past by some Japanese developers, but I wanted to create an engine for Heyuri from scratch. I call it Sumika, it's mostly made to act like SSP. The repo is open source, though it's not very great and there may be some bugs with it. It should support most ghosts as it is, but later on I may improve it to support some more ghost engines. Obviously it's all created with AI too...

I also machine translated some ghosts to put on Heyuri. I hope it won't upset Japanese creators of the ghosts if some are still around - my intention is merely getting more netizens to have fun with what they have created. There are around a dozen ghosts to check out right now, I can expand the list later on. You can also feel free to make requests like "kaguya-san, can you also translate and add this ghost I found online please!" on bulletin boards.

It's enabled for everyone by default right now. It's possible to iconify the feature to tuck it to the corner of the screen, or turn off completely from its controller page. I may also eventually disable it being on by default, making it an opt-in feature of Heyuri. If that happens, you would need to enable it on the controller page. I'll add the controller page's link to the frames in the meantime.