That could be it, but then again, he could just be glad his socially awkward daughter has a friend, and also understands that his daughter is, well, socially awkward. He was also over the top happy when he first found out Koyuki's club would get a new member, without knowing almost anything about Amano back then. Even without the whole blatant gayness, it is obvious Honami does not make friends easily, and for that matter I do not think she even has any beyond Amano. Gay or no gay, of course he would be supportive.
You forget that other people already asked Koyuki out to the festival. The manga starts out making it a point that Koyuki is pretty popular. A lot of Koyukis reluctance comes from not wanting to offend the people she already turned down. If it was about supporting just friendship why doesnt dad encourage Koyuki to hang out with the people who asked her out instead of forcing her to ask someone else?
You do realise she was not shown to have a single friend before Amano showed up, right? She is not just reluctant to offend, lol, she is also painfully shy and socially awkward, something that her father knows. The guy was practically jumping when he saw his daughter would have another club member, and Amano was almost a complete stranger to him at that point. As I said, gay or no gay, of course he is going to be supportive, even if he sees them as just friends. He could be cluing in on the gayness, but I do not think that it can be argued as the only possible view, and to be frank, I do not even see it as being more probable.
last edited at May 17, 2018 10:15PM