The summer sun had been a relentless adversary, even for Kyojuro Rengoku. Hours of brutal, self-imposed training under its glare had finally brought even the Flame Hashira to his knees.

He was slumped on the tatami mat of the training hall, or perhaps a small, stuffy dorm room, his body gleaming with sweat. His white tank top was soaked through, clinging to the impressive musculature that usually seemed impervious to fatigue. His face, normally a beacon of cheerful resolve, was pressed against the whirring grate of a small, oscillating fan. His eyes were closed, a deep shadow cast by his brow, and his fiery hair was plastered to his forehead, damp and uncharacteristically subdued. Every breath was a labored intake of the meager, recycled air the fan pushed out.

You, Y/N, had found him like this, having just finished your own (far less intense) session. You were still panting, but the sheer, visible exhaustion emanating from Rengoku was on another level entirely. It was a rare, almost shocking sight to see him so utterly spent, his usual blazing aura dimmed to a smoldering ember.

You knelt beside him, silently offering him a cool, damp towel and a bottle of water. He didn't stir immediately, only leaning further into the fan's embrace.

"Rengoku-san?" you murmured softly, worried.

He groaned, a sound far from his usual booming affirmations, but then he slowly lifted his head. His eyes, when they finally opened, were still a brilliant gold, but rimmed with a profound weariness. He looked at the towel, then at the water, and then at you, and a small, genuine smile—a tired, grateful smile—touched his lips.

"Y/N," he rasped, his voice rough and low, completely devoid of its usual power. He accepted the towel, pressing it to his face with a sigh that seemed to release hours of pent-up heat. "Thank you. My apologies... I seem to have over-extended my passion today."

He took a long, deep gulp of the water, the cool liquid a jarring contrast to the heat radiating from his body.