Hello! This is my second ever fanfiction, months apart from my last. Safu doesn't get enough love in this community, so I thought I'd write something for her. I'll probably post a belated Nezushi valentine's fic later!

She'd watched him all of her life.

From the moment they first met as toddlers, both geniuses in the school's gifted program, Safu's eyes never trailed off of Shion's figure.

Shion was the subject of her admiration, friendship, and a deep, yearning affection that grew like a tree in her heart over the years she'd known him. She was only 11 years old when she realized that the burning, fluttering sensation she held in her heart towards Shion was one of love.

Safu was always scientific. She looked at the data, the facts, the charts and graphs that make up life. Humans and their behavior are a set of numbers and letters, chemical compounds of the same composition. Each human is the same, made of the same materials and data as everyone else. Even Safu was just like all other humans, she'd always thought.

But Shion was different. She could never see him as just another mundane, identical lifeform. Safu didn't know why, but she couldn't help but see him in a different light. He was a rare specimen, a prized and treasured being that Safu held dear to her heart and examined closely.

She was always content just watching him. Observing. Gathering internal data on how this being called Shion functioned. But she couldn't help but want to get closer, to feel his arms around her, to breathe in his scent and embrace him. She knew what sexual attraction was, of course- she specialized in physiology. She was 12 when she first had those sorts of feelings towards her best friend. She never told him, not for three more years. She knew he was young and innocent, too naive to realize her advancements. Besides, after his 12th birthday, something within Shion changed. A wall had built around him, as high and impenetrable as the one around the city. As desperately as she wanted to get in, to know all of Shion's secrets and desires, she quickly realized it was impossible. But by the way he looked off into the distance whenever they met up, staring yearningly at some far away person Safu might never know, she knew that the spot she wished to take in Shion's heart had been occupied.

She was satisfied with that. So long as she could continue being by Shion's side, staying close and observing him, she was glad. As much as she wanted it, she didn't need his love. She just needed his friendship and support, and she was fulfilled.

Then, at 16, she was offered the chance to study abroad in No.5. It was a great oportunity, and she couldn't pass it up. But of course, that meant leaving Shion behind. Safu knew her priorities- learning, heading towards her future goals and a steady job, were things far more important than staying behind for some boy who didn't even see her the way she wanted him to.

She decided that then would be the proper time to confess her feelings. Just before she left, so that Shion wouldn't have time to think too deeply and would have to answer her honestly about how he felt. Even if she was rejected, which she calculated had at least a 94% chance of happening, she would be satisfied simply being able to get her feelings across to the airhead before she left.

And so, being ever straightforward and direct, she said what she thought would most bluntly get across her desires towards her male friend.

"I want your sperm."

Of course, rejected. She hadn't held much hope in a 6% or less success rate. Honestly, his innocent and kind refusal, saying he would wait 2 years, was rather adorable. That was just one of the things she loved about him. Of course, she had long ago made a list of all Shion's traits, circling the ones she found desirable, and there were too many things to count on two hands. She knew everything about Shion, from head to toe, except of course what happened on his 12th birthday. She knew that whatever occured that night was likely the primary cause of his rejection, along with other factors including his chastity and airheadedness.

When Shion ran off, not even giving her a proper goodbye and all to chase a filthy rat, Safu knew it was related to that event four years ago. That look in his eyes as he dashed off, the urgency and desire that emanated from his body, she had seen it before whenever he'd spaced out reminiscing about an event she could only dream of understanding. Still, to get so excited, so passionate over a simple rat, whatever had happened that night must have truly affected him to the core.

It was then Safu knew it wasn't her place to interfere. That spot in Shion's heart was too closely guarded, too deeply filled for her to come close. She knew that eventually, when he was ready, he would tell her. When he could, he would introduce her to whoever this person was that so occupied his heart and mind. Until then, she would have to remain as she always was- simply an observer, hoping that Shion found the happiness he deserved.