It’s tagged “Gainax Pose” on Pixiv and the pose indeed looks familiar, but I can’t remember where it’s from. Do we have a tag for that pose?

It’s also tagged “ass visible from the front”…

Edit: The tag’s gunbuster_pose. Thanks cityofvictory.

Asuka Langley Souryuu from Neon Genesis Evangelion (A Gainax series) commonly uses this pose I think.

I think it's more tied to the leads from Gunbuster and Diebuster.

Western fans normally call it The Pose or That Pose (proper noun) in my experience.

And it is most certainly from Gunbuster as the main origin. (Thanks to whoever added the right tag)

Having never seen Gunbuster, I feel a definite Tengen Toppa Gurren-Lagann vibe from this.

The main originator of the gunbuster_pose is actually the Getter Dragon from Getter Robo G. I believe it happens in one of the movies; the Getter Dragon emerges from underwater with its arms crossed. I can't find a screenshot or a video, unfortunately.