Found something on a Danbooru raid.

Well that should whet your appetite for this absurdly awesome version Miku… I have no idea when or why but DO WANT! I was lurking around an irc channel and someone mentioned danbooru and ads, something I’d never seen before (thank you lolifox, for blocking that crap) and I started two day raid, yesterday I just wandered around comparing the place to moe.imouto and then stumbled across brs miku and proceeded to grab every picture I could possibly find of her. (Today has consisted of mostly Saber searching, some Vita, some Illya and now Agrias…)

Apparently it spawned from a niconico video. (youtube version for the nico-less) Checking the comments there’s a claim that it’s not an alt. Miku but an original character. Looking at her though either it is an alt. or very heavily inspired by here.