Not really sure why Sanjuurou had Mikako the one that looked unrepentant in the cover spread. She's the one that showed to be the most contrite in her story. I wonder if she ever tried to tell her friend, "Y'know, what you're doing to him is kinda mean..." Probably at that time, her friend wouldn't have listened.
Ooh, a crossover between 3 different releases? Intriguing! So they're actually all friends?
No better excuse to go and re-read all 3, I suppose!
All 3 of them were rather interesting stories, so this little crossover was quite the entertaining read.
I must admit, I don't know how original this type of cross-over is but you don't see it too often, esp in hentai. And indeed these three happen to be friends. I'm not surprised.
As 'Split133' indicated, this probably means that one book (or more) from Sanjuurou is right around the corner. In which case, There Can Be Only One Conclusion:
"Ladies and Gentlemen, ..... LET'S GET READY TO RUMBLEEEEEEEEEEEEEEEE !!!!!!!!!!!!!!!!!!!!" - Michael Buffer.
Tbh we need more of crossover like this doujins