Back Story:

Sai and Hiro went to elementary school together. At that time Hiro was in his softer phase so he was often mistaken for a girl.

One day some kids were picking on Hiro calling Hiro girly and pulling his long hair, and Sai came in to protect him and beat the bullies away.

Renji: Look it’s that weird girl.

Kite: Let’s go get her.

Kids poking and pulling at Hiro.

Hiro: Stop. Please… Stop.

Hiro was pushed to the ground. Tears ran down Hiro’s face as he pleaded for them to stop.

Sai: What are you doing!

Sai jumped over and kicked Renji to the ground. Kite tried to grab Sai off him, but then Sai turned and tackled Kite to the ground.

Thump

Sai then started punching him as the other kids ran away screaming.

Sai: Leave her alone! Why don’t you pick on me if your tough!?

Renji got up and pushed Sai off Kite, grabbed him up, and ran away. Sai was panting…

Huhuhu…

He went over to Hiro and helped him up from the ground. As Sai wiped the tears from Hiro’s face, just then Hiro looked up at him.

Sai: Are you o…

Ting

At that moment like a chime going off, Sai had gotten lost in Hiro’s eyes, they had captivated him.

Pretty…

Sai thought, not knowing that the words had escaped his lips.

Hiro blushed and stood up.

Hiro: Thanks.

Sai: No sweat. They needed a good beating.

Hiro looked at Sai with the biggest eyes and admonishment.

Sai: Are you hurt? You, Okay??

Hiro: Yes. I’m fine. I’m used to it.

Sai: Say, why do they pick on you anyway?

Hiro’s face had flushed as he pulled on the bottom of his shirt and shied his gaze away from Sai.

Hiro: Well… The kids always say I’m weird because I act a little different.

He fidgeted his fingers and looked down at the ground.

Sai: It’s cool with me. My grandmom always says it’s okay to be different. So, you’re okay with me. From now on I’ll protect you, and when we get older, I’ll marry you so no one can mess with you.

Sai gave Hiro a big smile, and tears flowed once again from Hiro’s eyes.

Sai: I’m Sai. Omoide Saigo.

He gave off a big grin and stood chest puffed out and proud.

Hiro: Oh… Hi. I’m Saikou. Saikou Sh-

At that moment, the teacher had come out to the yard and called all the kids back inside.

Sai had taken off a few steps, running back towards the school, when he stopped and turned to Hiro.

Hiro was lost in thought at the words that Sai had uttered. The fairytale future that a promise bring.

If only that could be so…

Hiro sighed, slapped his cheeks, and nodded.

Hiro: Mm.

Hiro then ran behind Sai, and they ran hand and hand into school.

Sai vowed that he would protect Hiro and that they would always be together.

Sai is under the impression that Hiro is a girl.

From that moment on they were inseparable ‘til graduation.

In the end, Sai had moved away before entering middle school. And the two of them had seen each other no more.