I read a book many years ago about a people who were hermaphrodites or similar and I remember a part where a normal visitor arrived in their community and he spent the night in tent with a young man and during the night the young man changed into a woman and wanted to have sex with him but he wouldn't because it was just too weird....the situation she had turned into was called 'in kemmer' which was their way of procreating. I thought the book was called ' a wrinkle in time' but all searches have turned up a completely different book....has anyone else read it? and what is it really called? it was fascinating!
Bit of an SF fan, and the setup sounded familiar, so I had a nose around. I originally thought that it might have been a Piers Anthony(?) novel where the aliens can change sex, but (IIRC) they weren't humanoid - the main character was, and had had his conciousness transferred into an alien body.
Ta.....I googled that and you were right! it all came back to me, and think I'll read it again. That's why I was looking for it.....many thanks. I had rather got bogged down in the 'A Wrinkle in Time ' title, and could get no further.....