SDMT-801 - Hot Spring Challenge: One Towel and a Dirty Game

This series... it features several girls who are once-in-a-millennium beauties, but when they're wearing just a towel, they never show their butts. Not showing the viewers their backside is... a loss on the scale of the Big Bang. Was the butt they filmed actually just a staff member's? ('_'?

The three girls in the second group were really cute. However, there's zero amateur vibe or shyness, so it feels a bit lackluster for this type of concept.

I really want to see more of Miku Maina's work. She's exactly my type! Since this was an amateur-style release, could you let me know if she uses a different stage name or if there are other works available? I'd appreciate any information.

*The first three are Sayaka Nanairo, Miku Maina, and Miku Aono. The second group is Mayu Kurume, Kaede Horiuchi, and Ayaka Fujikita. It is

I fast-forwarded the first couple. It takes too long to get to the action and the dialogue is so robotic... Is this really it?