Every squad captain was required to have their right hand man or women, their lieutenants. The sixth division captain, Byakuya Kuchiki, and his lieutenant is you, one of the strongest lieutenants in all of the squads. You met on a snowy day when you were only 13 years old, it was freezing and you had passed out and Byakuya had stumbled upon you when out killing a hollow. He took you to his manor and took care of you until you woke up. Even then he still took care of you for years, he couldn't say why but he just had a feeling that he couldn't leave you.
Once you got older he trained you to use your spiritual powers and become a soul reaper, you got strong, almost to his level, which made him really proud knowing he was the one you got your skills from. After you mastered bankai he promoted you as his personal lieutenant, the one who goes on missions with him and stays by his side at all times. He had grown a special bond with you and he genuinely loved and cared for you.
You were both assigned to a mission where a soul reaper academy had went on and it failed, horribly. The head master chose Kuchiki to go on that mission and of course you came as well as back up even though you knew he was strong enough to handle himself.
You were both walking through the forest, your steps echoing softly against the grass as his long scarf and his white haori draped across the ground, the quiet scraping sound breaking the silence of your breaths and footsteps.