Writer of the Rocky Horror Show, Richard O’Brien, has said: “I believe myself probably to be about 70% male, 30% female,” calling himself the “third sex.”

Creator of the famous Dr Frank N Furter character, he told BBC Radio 4 that he knew from a young age he wanted to be more feminine.

“I was six-and-a-half and I said to my big brother that I wanted to be the fairy princess when I grew up. The look of disdain on his face made me pull down the shutters. I knew that I should never ever say that out loud again.”

For 50 years, he repressed the feeling but said: “you can’t just put the lid on things and pretend that they don’t exist.”

A decade ago, he started taking the female hormone oestrogen and since feels more comfortable with his body.

“It takes the edge off the masculine, testosterone-driven side of me and I like that very much. I think I’ve become a nicer person in some ways, slightly softer. For the first time in my life, I’ve started to put on a little bit of weight, which I like.”

He has also developed breasts, but O’Brien does not intend to have gender reassignment surgery.

“I don’t want to pretend to be something that I’m not. Anton Rodgers, the actor, said ‘you’re the third sex’. And I thought that’s quite nice. I quite like that position.

O’Brien says he ticks the ‘M’ box, but he “would quite like to have Other to tick.”

In an interview with PinkNews in 2011, O’Brien previously stated: “It’s my belief that we are on a continuum between male and female. There are people who are hardwired male and there are people who are hardwired female, but most of us are on that continuum and I believe myself probably to be about 70% male, 30% female.”

Cambridge University psychology professor Melissa Hines says there more than two distinct sexes: “I think that the research in this field suggests…there is not a gender binary, that there’s a range of gender, and there are many dimensions of gender and an individual person can be in a different position in terms of how masculine or feminine they are on each of these dimensions.”

James Barrett, lead clinician at the Charing Cross National Gender Identity Clinic said that, although society tends to think in terms of just two sexes: “It may well be that biological findings report that, in fact, everybody’s on a spectrum.”

“The same is probably true of sexual orientation. Most people don’t describe their own sexual orientation as being on a spectrum although actually, practically speaking, it very much is.”

O’Brien previously said that “society should not dictate gender.”