Somehow, this author gonna milk this manga to 300 chapters. Somehow, some way he is. And I'm not even going to hate on him for doing so. Gotta pay the bills somehow.
Y'know I hated this manga's concept at first because I felt that the people around the mc couple were forcibly makingthem into being swingers. But they seem so happy now, I can't hate on it anymore. 3/10 -> 6/10.
They're probably both guys.
I'm guessing that their family has a weird rule that if there are twins the younger one has to crossdress. And somewhere down the line the older one decide to do so as well for plot reasons.