Just because you see something on someone doesn't make that someone what you see on them. If it's still a majoritarily male in it's physical form then, by definition, if you're a man, it must be considered homossexual. But there is no problem on that too.
In this case he isn’t majoritarily male in his appearance. If you are attracted to the female appearance, and nor attracted nor repulsed by the testicles, you could be attracted by a trap without being homosexual.
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Homosexuality is about appearance, otherwise the word would completely lose its usefulness :
"Nobody" is sexually attracted by a abstract concept, nor by a particular kind of DNA.