I think they just have the same hairdresser

btw, where did you find that image? It's different on Indiegala and on Steam (and google can't find the game's indiegala listing on facebook at all) and a reverse image search can't find it either. The actual in-game protagonists look like this http://gtm.steamproxy.vip/sharedfiles/filedetails/?id=611236366

older discussion on this topic is here, no answer there

It was posted yesterday to Facebook.

https://www.facebook.com/IndieGala/posts/1863159523756867

Ah, ok, thank you! (Still no hits on tineye or Google reverse image search.)

At this point I should say that I am no way affiliated with "Power Of Love" or Indiegala except as a customer, and that I am not qualified to give legal advice. However, my opinion is this:

1. It is questionable whether that girl on the facebook picture constitutes copyright infringement, based on the comparison picture you posted. Maybe it does, maybe it doesn't; maybe a better comparison picture can be found. There's certainly some similarity.

2. If it is a copyright infringement, it is not clear to me who the infringer is: it could be IndieGala and not Yang Sun, given that right now, only IndieGala seems to be publishing that image. (Given the presence of the older thread, maybe Yang Sun infringed initially and then removed the girl from all images, and Indiegala posted one of the old images by mistake.) You write "why did you steal" and that's an accusation that may prove to be wrong.

3. I don't remember too much of the game, but I don't think I saw her in there, so "include her in the game" is likely also wrong if that girl only appears on the IndieGala game ad. Edit: I just checked the files in the game's "image" directory, didn't see her.

Since you are demanding the observance of the legal necessities, you may want to make sure you're not accidentally committing defamation.

For more iages of the character just google "Mami Tomoe." She's a character from an anime that many would consider one of the greatest anime shows *ever*.