
That is not what I call relevant and implicit.
If the character was shown making exercise in the morning and then arriving to class, and then the other one was shown taking at least the tiniest sniff before confessing (not just looking at him, but actually sniffing), then I would agree.
If at some point he had taken a shower and then the other one had lost all interest until he made a bit of exercise again, then I would agree.
If the one without the fetish has shown any kind of discomfort in the situation, for example when he has his armpit liked, and that would have been the think making him hesitant about accepting the other one's feelings, then I would agree.
But there is abdolitely nothing in here

I'm not that good at Japanese anymore, but 性癖 could be translated as fetish in this case. I'd probably translate the full title to "The guy who confessed's fetish is". But 性癖 could also mean inclination, propensity, disposition, and that would kinda change the title. But I'm not good enough to tell ¯_(ツ)_/¯

If it's not about translation then I'm almost sure is a problem of script rewriting.
When you write a script you always need to adjust it in severas ways, you need to take away the things that are not necessary, cut the story to the final length, and so on.
When I was studying script writing the teacher told us about the rule of "not throwing away the baby with the dirty water". You need to start cutting and, without realizing, you can end up cutting too much. He compared it to bathing a baby and when you throw away the water you don't realize you are throwing away the baby, the "importante part".
Probably in the original script there were some parts showing it better, but adjusting it to such a short length must have been hard.
Sooo.... What fetish? ( ̄∇ ̄")