A/N: This fic is for my best friend, Leazher ( u/4873458/Leazher), whose birthday is tomorrow (That is to say, 4 April. You are all to wish her a happy birthday! Otherwise I shall go from Chickenpony to DEMON and... and... be very upset with you!). She is a big ByaRuki fan, so I wrote her this as her present. Be sure to check out her work too!
Dearest Rukia
When I saw you for the very first time, something stirred in me that I had thought was long dead. I knew I had to have you for myself. And right there and then, as soon as it had healed, my heart broke again, for you were undoubtedly the one I was seeking: my late wife's sister, destined to be adopted into the family as my own sibling. I would never be able to love you the way I yearned to.
However, I am unable to contain myself any longer.
Rukia, I love you. I love you more than I've ever loved anyone or anything. I love you more than any man has a right to love a woman, much less his sister, and I always have. You have made me so much happier than I deserve to be and I hope that one day you will be able to be the same about me. You are the single most important thing in my life. Should the moon, the stars and even the sun fall from the heavens and the world be plunged into darkness for all eternity, I would be alright, as long as you stayed with me.
I have realized that there are some things that are more important than keeping ancient vows. So here's to breaking promises again and again, and making brand new ones to you.
Wishing you a very happy birthday,
Kuchiki Byakuya