I think Ed/Yeowoon/Tommy is asexual..meaning without sexual feelings or associations; asexual people can still experience sexual arousal, or romantic or aesthetic attraction, but they lack sexual desire and passion. It fits the story we have so far. He lost his virginity at 17 and his girlfriend at the time initiated it.On camera, he is going through all the motions and having all the proper physiological responses. I think he is drawn to McQueen because he recognized McQ has the ability to draw out sensuality, lewdness, sexuality in people and he both wants and doesn't want that drawn out of him...people are inherently afraid of change. As far as the gay sex goes, what he is struggling with is his own concept of masculinity not being homosexual or bisexual. Being the bottom is the same as taking on the woman's role b/c he is on the receiving end. His penis is obviously not relevant in that scenario. Also Chang is a red herring, I sense no ust with him and Ed..it is all one sided-Ed wanted a bro, chang wants that ass but is in denial.
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Walk on Water