This song lol got me thinking of the question-listen to it if you have the time. But seriously, I mean think of all the friend relationships. Ginny and Harry, Ron and Hermione, Percy & Annabeth, Jacob and Bella (Almost), & etc.
Most Helpful Guys
When you spend a lot of quality time with someone of the opposite gender that you enjoy being around, everything that connects the friendship together will make that bond you have with them stronger! Depending on how many common interests and beliefs you two have, along with physical attraction and having a favorable personality, that'll be the determinant between staying as friends to wanting something more. Out of my two closest girl friends that I know, I'll admit that I could see myself being a potential partner with them, however my desire for my current girlfriend is the strongest because we grew up together for a good nine years which makes me more attached to her!
Naturally, I would say it's difficult to be friends with someone of the opposite gender if you find them attractive but it's possible to be friends with them with effective communication and trying not to flirt too much. I just feel like the relationships that form from friendships are most healthy and will likely be the most successful ones too! In short, it's possible.
Guys and girls can be platonic friends. I have had several during my lifetime.
Most Helpful Girl
... those examples are fictional and only taken seriously by children
i find the disregard for the sexuality spectrum really distasteful