I wrote this fic annoymously tehehehe but the demibisexual/grayromantic main character spends this fic falling in love with his lifelong best friend and exploring everything for the first time. I was always liked the scene where he realizes demisexual is a thing:

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"I didn’t know I could be this emotionally attached to someone and it’s like realizing that is what changed everything. I’ve never wanted any of this before, I’ve never even been attracted to someone like this before, but now I can’t stop thinking about them. I guess I’m confused about how all of my feelings for them could change so quickly and how I can suddenly care so much about, you know. Stuff.”
He hesitated again, feeling a little bit embarrassed to be talking this deeply with everything to Julie.
“My tía used to tell me that if you’re not ready to say the word then you’re probably not ready to be doing it,” she teased.

“Sex!” Reggie blurted out, catching the eye of an amused older woman. “I’ve never cared about sex before, and I never felt any of this for anyone ever and now I feel so much it’s like I can’t breathe. I’m so confused and so overwhelmed and Julie you’ve got to help me, please!”
She tilted her head, like a confused dog.
“Do you think she could be demisexual -and maybe a little demiromantic?” She asked. He gave her a confused look, and Julie took out her phone, pulling up a Wikipedia page and his eyes went wide as soon as he saw it. “It’s kind of like being aro ace in that you usually don’t have a lot of attraction to people like that unless there’s a really deep emotional connection. You might know someone for a long time before you connect with them emotionally enough to be attracted to them romantically and sexually. You don’t automatically feel attraction to people, like how Alex and Willie were automatically attracted to each other.”
It was like someone looked up Reggie Peters in the dictionary and perfectly defined his love life for him.
“How is that different from how you and Flynn fell in love?” Reggie asked carefully. “You never knew you liked her like her for a long time.”
“Well, I guess…normally you would have attraction and desires, even if you didn’t want to act on them, but it sounds like you never do. Even though I recognize now that I always love Flynn, I was absolutely convinced at times that I had crushes and feelings for other people too, but it sounds like you've never had that."
“Nope. So I can be bisexual and demisexual?”
“Yup! You could be demiromantic too or grayromantic maybe," she explained. "Asexuality and aromanticism are a spectrum, there are all sorts of terms that fall under it. It sounds like you could be bisexual, demisexual and grayromantic or demiromantic.”
“Huh…” he was trying to figure out if he felt less confused than ever or more confused than ever. “So it takes three labels to explain my love life? Typical Reggie.”
She looped her arm with his as they continued on down the sidewalk, his mind reeling from this revelation.
“You don’t have to label yourself at all if you don’t want to,” she assured him, "but it can be helpful for sorting through what you feel. Without outing anyone, let’s say that I’ve talked through this before and people have found it helpful in understanding themselves. Plus. there are all kinds of communities out there online, you might feel a little less alone and confused if you do some researching about it."
Were there really other people who felt this way? All his life it felt like he was the oddball, everything was so complicated in his head that it felt there was no way anyone else could be going through this.

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