Talk:Kenkou Cross Q&A/@comment-24664052-20150321100435/@comment-12776-20150421041839

...or they're actually two good friends and really love double peneration. Although the mamono would be uncomfortable at first, it shouldn't be problem.

At this point, I'm pretty sure that Kenkou put the monogamous rule for mamono to avoid tragedy of cheating wife or lossing your lover to NTR douchbag. So if all three of them are fine with it, then I think it's possible to see them live together.