Looking for an old hentai - pic for attention

I saw an old anme I'm looking for. Here's what I remember
There was a girl and a group sex scene in like a bunker or a gym. hte girls wanted to proove she was cool and not a virgin and sending pics to friends.
I believe she put an ad online to try sex and then got soooo many people.
One unusual thing about it was a double vaginal penetration.
Can't remember anything else.
Thank you !