Could someone tell me the name of the set where this pose comes from?

SKYNET

Could someone tell me the name of the set where this pose comes from?

felis

It might not be that the pose exist in a pose set, and just is posed to get what is wanted.

crosswind

There're quite a few products having the similar pose like this... and it'll be pretty easy to tweak the pose as per your need just with a couple of clicks ~~

for instance,  this one : https://www.daz3d.com/adorable-kawaii-poses-and-expressions-for-genesis-8-female-s in the 3rd small promo pic...