Responses
Lust involves attraction by definition. I'm not sure what the word "genuine" is meant to do in your comment. There is no queer council around to authenticate the attraction by a kind of scale that proves it has left the straight zone. In fact there is a ton of writing about how patriarchy cultivates gender relations in which men only view women as objects of desire/lust and yet this does not seem to "invalidate" their heterosexuality. (To be fair, some argue that it does lol.)
Isn’t bisexuality or bicuriosity about being attracted to both sexes? While Eunsan does seem to be bisexual, I think his encounters with men stem less from genuine attraction and more from a desire to satisfy immediate lust.