Couch is suddenly HUGE!
It's certainly a Big Comfy Couch. (I'm sure I just ruined someone's childhood)
I like how honest this feels. It's not full of the usual ritual phrases we see in yuri, or complete ignorance about sex. It's even got girls laughing during the act which really speaks to me, since that relaxation and intimacy are really part of the mood. Not something you really see much, if at all, in the Japanese stuff.
True, this is nice that way. I found it pretty fun and engaging.
As to Japanese stuff . . . I can only think of one major exception, really. That would be Maka-maka. By the same author as Virgins' Empire, but much more adult. It almost systematically breaks most of the conventions of yuri manga in specific, romance manga in general, and sex in manga. The art style is odd by manga standards--it's all in colour, it has a more three-dimensional look and the face and body types are somewhat unusual. Most relevant to this, the two leads (both girls) have sex a lot and are generally laughing through half of it.
It's really worth taking a look at IMO. The attitude towards sex, friendship, romance and stuff are very different from how you see them in normal manga, and the social environment seems neither sugar-coated nor sensationalized. There's more to it than meets the eye. Look at it one way and it's just this manga about two friends who have sex a lot. But I feel like there's a challenge in it to a whole lot of conventions, both manga and social.