Hey everybody.
I've seen a few images of the same style as this Koishi going around, and did a bit of digging.
While several of the images I've seen so far are really not post-worthy, this does seem to be a little bit of a meme, inspired by this twitter post.
In lack of a proper name, I've tagged the images we've got so far as how_to_hold_x_(meme). Feel free to change it if you think something else would be better, there's literally only two posts on danbooru right now, by my reckoning.