Sexual Relationships 
Sexual Health 
What's one giveaway that the story you're reading is probably the product of a female character being written from a male author's perspective?
Boobs.
Men tend to describe their female characters as overly-aware of their bodies and how they move. There is a lot of talk about breasts, how 'full' they are, weighty, and sensitive. The women are usually described as 'lush' and 'voluptuous' as opposed to women written by women, who are often described as thinner and frailer.
It's funny how many male authors think a woman’s nipples are able to express emotions. I have seen an awful lot of 'hardening in anger' as well as 'hardening in fear.' Hell, even just hardening because she saw someone attractive.
Like a couple of tiny twin boners.
Women written by men also tend to be more aware of their effect on men, and more confident, and yet also completely unaware that they are stunningly beautiful. A classmate once actually told me: ‘a girl who knows her value will never give assholes a chance’.
Maybe he was onto something...
WOMEN WRITING MEN
Men written by women are usually brooding and withdrawn. They often have a mysterious, painful past that makes it difficult to trust the heroine as they go through many layers of emotional turmoil.. The physical descriptions of men seem focused on eyes, jawlines, and torso-muscles, in that order. There is almost always a scene where the man changes his clothing/armor in front of the girl, and she blushes when she notices his “sinewy, muscled back.”
Despite their withdrawn personalities, the men usually light up around children, and get along wonderfully with them. The children almost never show any inherent knowledge of ‘stranger danger’ and tend to love and trust the men instantly.
The men almost NEVER flirt with other women, or even look at them. Usually a very traditionally sexy woman shows up at some point to seduce him, and he publicly rejects her in some way, showing his devotion to the “plain, scrawny” heroine. Sexual encounters are more tentative and emotional…
Think of a man who nervous, shy, and gentle. He usually has to reassure the heroine that she is, indeed, beautiful- especially the first time he sees her naked.
Even if it’s his first time, a female author will typically depict him as being amazing in bed by providing a detailed description of him trying to pleasure the lady first. Rather than thrusting a few times, coming, and then going to sleep.
I remember a scene in a Mercedes Lackey book where this couple is about to have sex (which guy has a lot of experience with), while it's her first time. He goes down on her and brings her to orgasm before any PIV happens.
When he comes up, he grins and says that a previous partner of his had advised him to do that with his ‘next sexual partner’ so that their first experience of sexual contact would be one of pleasure, rather than discomfort. What a lovely relief from all of the ‘bLoOd oN tHe ShEeTs’ nonsense that usually characterizes sex in fantasy/history books.
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