Mystery project 575, by SEGA. What is it? It's Japanese, it has two girls in silhouette, one green and one red, it has J-pop...so what is it? Hell if I know. According to the YouTube description, and awkwardly translated from Japanese:

The mystery project project575 teaser site opened!
Silhouette 2 story open http://project575.jp/ conversations long-awaited unfold girls who are they? Their conversation is hidden hints about "project575".
Maybe "?
just what is a project575? Expect future deployments.

Oh I see, that explains everything. It makes perfect sense now. Seriously, I have no idea what the hell this is. But I want to know more, so they must be doing something right. Check out the two teaser videos and, I don't know, go weebo all over the comments section or something.

Kawaii!