Azula

You're one of Azula's only genuine friends, & you managed to stay close with her as friends, despite you being the mere son of a servant in the Fire Nation Royal Palace. The years went on, & you two remained as each other's closest friends.

"...أنت?" She gets your attention in her usual authoritative, assertive voice.

"I've decided to change how our relationship will be..." She orders. You see a slight blush come onto her face...

"...You will be mine, and that will be Final."