@centrox,
Good story. It took me a long while to figure it out, but IMVMO (in my very male opinion), when they "sense your manhood" as you say, they are usually trying to send a clear non-verbal cue that they would appreciate a piece of it.
That, or they're testing the equipment to assess whether or not they ought to have a piece of it.
I have a similar story. In highschool I had a very close female friend, we were always together after school and at recess, really enjoying each other's company a whole lot. She was firmly standing at the center of my "friend zone", as you guys would say. When male friends would ask me if we were together, I would say "no, just friends".
Copain-copine, as we say. As far as I was concerned, it was by all account a beautiful friendship. Now of course it dawned on me that if she was always sticking with me like that, maybe it was not for my ideas about Patty Smith or sci-fi. Maybe she loved me more than I was ready to love her.
Years later, still clueless, I visited her for a couple of days in a small city by the ocean where she was living as a sole parent of two kids. I knew the two fathers from highschool, assholes who had beaten her in one case, and dropped her when she got pregnant in the second case. It's a sad story. They were nevertheless happy enough, in a smallish but fine apartment -- my friend had a steady job, had become a judo instructor, beautiful kids. We had a nice dinner and chatted and chatted and then later went to bed. There was a couch in the corridor but she invited me in her kingsize bed. I started to wonder if she had something in mind. So, we're both laying there and I stay there totally rigid, me being me, timid to a fault, unable to vocalize any feeling or desire to any woman, even to a long time friend.
Particularly to a long time friend, I should say. I didn't want to lose her friendship at any cost, couldn't risk to come across as just another asshole trying to abuse of her hospitality... I made no move whatsoever, tried to stop thinking about it and sleep.
Then she started sobbing. I didn't know what to do. I asked what was the problem, she kept silent, crying on her side of the bed. I thought she was afraid of me, she was scared I would rape her, knowing what she'd been through with the father of one of her children. I kept trying to speak about it, without touching her. At some point she stopped and said it was nothing, and then i went to sleep.
I now think she was going around a bout of self-depreciation along the lines of "I brought him into my bed and he doesn't want me. If it was any other woman he would be all over her right now... I must be the ugliest girl in the universe... damaged good." Something like that. I should have stroke her hair, taken her hand, cracked a stupid joke, cuddled her, massaged neck. And more if necessary. But she never asked, and I couldn't guess.