Mikoto Mis*ka's petite breasts over here, busty Misaki Shok*ho over there.
Between them is the world's unhappiest guy, Toma Kam*jo.
One day, while he's enclosed by the girls, a mysterious power transposes their souls.
^ Taken from the english dlsite http://www.dlsite.com/ecchi-eng/work/=/product_id/RE154779.html, man its like someone just machine translated and c/p it. But it is tagged as transsexual on both english and japanese sites so.
It is gender bend because of the twin misakas and misakis, probably. But i have no idea if its possession or bodyswap on the non-twins parts as the guy seems to look like Kamijou from the hair style atleast.