Thank you for passing by my table again! MEFCC was a success but very stressful at the same time ^^
Now to answer your question;
I never think of Black and White as a romantic couple or the story as shounen ai. I often talked about how I’m surprised when people think they make a good couple when I see it would be too unhealthy and totally lacking any chemistry.

I like to write about friendships and I’m too biased and committed to the topic (childishly and stubbornly sometimes) that romance never registers in my head even though I know romantic couples can be/ are friends and the other way round.
I think there isn’t enough stories that talk about platonic relationships and only that, especially same-sex friendships. Even more rare when it’s not just some casual friendship but one that takes a spiritual level. Many people when hearing the word soulmates, think lover/spouse/significant-other, but sometimes a person who inspires you, who is like a muse to you, someone who you feel like is you but very different from you is what makes a soulmate. Across history I read about scholar-student, artists, friends, siblings, half-siblings, etc, that were soulmates and only plaotnic.
Such relationships inspire and attract me.

Now about your last question, the answer is sure “no” if you’re asking about the present time onwards in the story. Neither will suddenly fall for the other, and just as it is in the story; Black isn’t interested what so ever in romance, and White was (is?)seriously serious about Lana and at some point had seen/planned his whole life with her.

But, if we were to talk about the past of the boys (maybe for a couple of days in their teenhood days), and because of what I just said about the majority thinking “most important person means the one I love and want to marry”, (a certain) one of the two will wonder if it’s “love” and not out of a real feeling, but out of 1. The changes they go through in that period 2. Their sucky lives which results in needing each other more which can all be a blurry mess 3. People around them misunderstanding their closeness. And all this can be a lot for a teen to handle.

It needed one of their good old heart-to-mind talks to turn the whole incident into an ongoing joke from one part to tease the other for years and years to come.