Today, I was casually browsing my X timeline when something happened.
I've belatedly become a fan of Super Kaguya-hime! Their official post was reposted by the official account for the anime "Oshi no Ko," so I took a look to see what it was...
What?!
Could this silhouette possibly be Mem-chan?
There was a description mentioning "that idol," and since it was reposted by the official "Oshi no Ko" anime account and Rumi Okubo, a friend of Mem-chan, I think it's safe to say it's confirmed!

My absolute favorite little princess! | 袮夜†大切で大好きな愛する最愛の嫁のルビーとpair's post