Only in Japan.

Anyways, came across this character when browsing Umamusume art on Pixiv. They were drawn consistently indicating it was probably fanart of somebody's OC. So I went looking and found out it was basically an Umagirl version of Hayagriva Guanyin... drawn as part of a series of commemorative seal stamps (shuin) issued by the Osamuhouzan branch of the Jousenji Temple.

Wasn't sure it was exactly a good idea to tag the temple and use it as the copytag and the chartag qualifier (as opposed to using original and then the artist's name as the qualifier), but people are tagging posts of this character with Jousenji_Temple and the usual shuin websites and forums has this grouped under their Jousenji Temple section (where they are apparently "hot" topics of discussion), so I went with this approach.

I 've wanted to upload some of these ever since I found out about them in early 2020 but was reluctant since they are mostly photos, thank you for enriching danbooru a little.

不失者 said:

I 've wanted to upload some of these ever since I found out about them in early 2020 but was reluctant since they are mostly photos, thank you for enriching danbooru a little.

You're welcome.

I hope I managed to pull the highest resolution version because Instagram is kinda of a pain to work with.