Sokka began to prefer Toph's company over Suki's on moonlit nights.
Even after he'd spent the whole day holding Suki's hand, whispering softly in her hear, cracking jokes to hear her laugh- if it was around the full moon, he would slip away and sit on a smooth stone bench outside the Fire Nation's palace. He would tilt his head up and gaze relentlessly at the glowing white sphere overhead. Sometimes, dark clouds would glide by the moon, caressing it, acting as a foil to its light.
Her light.
Inevitably, Toph would stroll up and perch on the rock beside him, yawning loudly as though Sokka had personally dragged her out of bed. She was still wearing the crimson and black outfit she'd stolen on their first day mingling with the Fire Nation. Sokka had once told her the red matched her personality more than her green and beige outfit had- it was fiery, bold. She'd just shrugged and reminded him for the hundredth time that she was blind and therefore color held no meaning for her.
She was blind but not ignorant. She could sense a pattern in the days Sokka sought refuge in the garden at night, acting much more subdued than normal. However, she couldn't see the phase of the moon, and she only knew the slightest bit about Princess Yue, and that from a horridly inaccurate play. Rather than demand an explanation, she just kept appearing by Sokka each time, keeping him company without saying a word.
Only once had she spoken. It was on a night when Sokka had become accustomed to her showing up and, admittedly, found comfort in her being there. As the moon sunk lower in the sky, Toph had said, "I only know what's on the ground. Everything I can see through vibrations has to be connected to earth. That's the only reason Twinkle Toes beat me in our first match. But people look up at the sky all the time and say it's beautiful. You're always looking up at the sky at night, but I don't think it's because you think it's beautiful."
Sokka had taken a few moments before responding. "No... It's definitely beautiful. The most beautiful thing in the world."
"I don't think it's technically 'in the world,' Sokka." A hint of Toph's typical teasing tone had made him smile.
"Still." Yet he couldn't bring himself to offer an explanation of his actions, not that night or any other, but she never pressed him. An hour or so before dawn, he'd stand up and they'd walk side by side back into the palace for a few hours of sleep. Suki was extremely busy with the Kyoshi warriors, who were temporarily being trained near the palace as the post-war days continued, and didn't know about Sokka's nightly habit, didn't have time to question why some days he was too tired to come see her.
Maybe a better phrase would be "too confused." He knew exactly what Yue and Toph were to him. Yue was his sky, his moon. She represented the pinnacle of sacrifice and love. Toph was his anchor, bringing him out of any depression nights of full moon brought about and reminding him of how lucky he was to have such great friends. Suki was a different story. She cared about him, and he wanted to make her happy, but they kept drifting apart. Suki was a Kyoshi warrior intent on protecting the palace and everyone involved in the Harmony Restoration Movement. Sokka fought when needed to but found himself more useful in strategizing and guiding others. Sometimes it seemed that Suki was just his best friend who he happened to kiss.
Anyway, Sokka was just fooling himself. He didn't know what exactly Toph was to him. Their playful banter, their desire to protect one other, the fact that his life felt strangely empty when she wasn't around... He was conflicted about his feelings but tried to tell himself it didn't matter. After all, Toph was so young. There was no possibility with her but friendship.
But. The war had changed them all. It had forced them to mature, to shake off their childhood in order to save the world. Toph had stopped being a child when she disobeyed her parents and joined them on their quest. She had shown her pure talent as an earthbender when she harnessed control over metal and had risked everything on the day Sozin's comet had arrived, coming close to death. Sokka could still feel her tiny fingers grasping his own tightly. His heart had been pounding wildly as the soldiers came closer. For a few horrible moments he'd thought that he was going to fail Toph, and that she would actually die. But then Suki had showed up.
Suki kept showing up in his life, like a trusty boomerang. He thought he'd never see her again after leaving being Kyoshi Island so long ago, but before long she'd become a part of Team Avatar. It had thrilled Sokka to be with her again and to feel her lips against him again. So why did he hide certain things from her? True, he didn't want her to be jealous that he was still dedicated to Yue's memory. But mostly, he felt like she just wouldn't understand and that she would try to make him talk through his pain. Unlike Toph, who would scoot closer to him and hum an Earth Nation melody over the cicadas' chirping.
Sokka was torn. Suki. Toph. Yue. Suki. Toph. Yue. So one night, he decided to make sense of his feelings, to end the debate in his heart, and that the only way to do this was to speak to one of the three he cared for most.
It was a full moon and as always, Sokka left the palace, but this time he veered away from the garden and stood by the narrow river that ran nearby. He looked at the reflection of the moon in the water and then straight up at it. "Yue..." he whispered, his voice nearly drowned out by the crying insects around him. He was sure she could hear him, though. "I- I miss you." He squeezed his eyes shut for a few moments, reopening them when his breathing calmed. "I guess I'll always miss you. Um... I need your advice. Maybe I shouldn't be asking you, but, well, I feel like you wouldn't mind. It's Suki. And Toph. I care about them both, Yue. So much. But- how can I know which one I love more?" He thought back to his final days with Yue. She was so incredibly brave. She'd given her life for the people she loved so dearly. She'd called it her duty, but it was also love.
Love. Maybe that was it. "The person you'd die for is the one you'd live for, right?" Sokka murmured. Memories filled his mind- rushing to Suki as boulders were falling towards her, pressing his body against Toph's to keep her safe from the explosions about them, holding onto her as she dangled miles above the ground, wondering if there was any chance of saving her, even at the cost of his own life... Yes, that first memory had been of Suki, but that was during a time soon after Yue's death, and he was still feeling guilty over his inability to protect the princess. His desire to protect Toph was as strong as ever, and he knew he would give up everything if it meant avoiding the agony of seeing her hurt.
"Is that the answer then, Yue? Is it Toph I love most?" And when he said those words out loud, like his heart had been screaming at him to do for weeks, it felt right. With the burden of indecision falling away, Sokka even smiled. "Thanks, Yue. I'm certain now. But, how do I break this to Suki?" he fretted.
"Giving up after you finally admit your feelings, Sokka?"
Sokka whirled around. There was Toph, standing proudly with her hands on her hips. She was smirking at him, and if he wasn't mistaken, her cheeks were colored red. "Toph! Uh- I-"
"Save your breath." She padded closer and slowly her smirk turned into a genuine smile. She jerked her hand up and Sokka felt two small pillars of earth hit the back of his knees, forcing him to crouch. Toph leaned over, kissed him lightly on the cheek, and turned away, definitely blushing at this point. Sokka straightened up and grinned.
After all, Toph just looked so beautiful in the moonlight.