Agree. It's a bad habit; a "vice".
You can be a virginal 13-year-old boy who realizes that has his male friends get interested in girls, he is not getting interested in girls at all, but rather interested in the other guys, in a way he finds confusing and emotionally tumultuous.
This can go on for years without him saying or doing a single thing that's "gay."
He has not habits of vice. He is not deliberately fantasizing. He is no going to gay porn sites. He is not secretly imagining himself bodily entwined with this guy or that one. He is just feeling unbidden attraction.