A/N: This was pretty much written in the spur of the moment and submitted to ME's April 2008 challenge "Lonely Ol' Night". It's my first time writing these characters in anything other than quick cameos; I apologize if they're grossly OOC.

"Whatcha doin' out here, Prime?" Ironhide asked softly, finally tracking down his elusive commander standing on a ledge on the flank of the volcano, just above the Ark. The old warrior had not really been surprised that Optimus had decided to be difficult to locate this evening—he'd been a little off the entire day.

Oh, it was nothing that any of the rank and file would have perceived; Optimus was nothing if not subtle about when he got into a funk. Ironhide thought that perhaps Jazz had noticed, but then, there was little that escaped Jazz's sharp optics. Ironhide himself had only seen it because of his long-standing friendship with the Prime.

Optimus barely glanced at him as he stepped onto the level ground of the wide ledge, almost immediately returning his gaze to the star-studded sky without speaking.

"That bad, huh?" Ironhide mused aloud, walking over to sit on the ground with his legs hanging over the edge of the cliff. They remained in silence for some time, watching the slow wheel of the stars through the heavens, and then Prime finally vented a sigh and moved to sit beside him.

"Do you never wish for this war to be over, old friend?" Optimus asked quietly, the weight of millennia of harsh responsibility straining his voice.

Ironhide turned to stare at him. "Well, sure I do, Optimus!" he said, surprised that his leader would think otherwise. "I mean, I don't mind bustin' up a few Decepticreeps now an' again, but nobody likes to think he might spend the rest o' his life fightin'."

"Hmm." Optimus returned to his contemplation of the constellations. Orion was vividly bright against the velvet sky; the irony was not lost on Ironhide.

Too many reminders of what he lost, he thought ruefully, too many distractions. Ain't no wonder he gets in moods like this. He regarded the big mech next to him thoughtfully. Too often Optimus bottled what he was feeling up until it ate at him like rust—and it had become Ironhide's job, over the millennia, to bring him back out of it again. No one else was suited to it; no one else saw him as just a mech, like any other, rather than their infallible Prime.

"Yer lettin' it get to ya again," he said carefully, laying a surprisingly gentle hand on his leader's shoulder.

Optimus gave him a wryly amused look. "You know me too well," he replied mildly, though there was an edge to his voice that said he wasn't really sure if he liked that Ironhide knew him that well. Prime didn't like to let anyone know how much the burden of leadership weighed on him, not even his closest friends. Ironhide was perfectly aware of Prime's need to be a pillar of strength for the rest of them—he just wished that he would stop letting it drive him to neglect himself.

"Someone's gotta keep an optic out for ya," Ironhide dared to tease the bigger mech gently, "otherwise, who knows what kinda trouble you'll get yerself into."

"Hmph," Optimus snorted, optics twinkling. "Less trouble than you'll manage to find yourself in, I'm sure," he murmured. He laid his own hand over the one on his shoulder and then, tentatively, slid it up the red arm to grip Ironhide's own shoulder. Ironhide stilled.

So that was what it was to be tonight, then.

Prime didn't often ask for any kind of physical intimacy; the first time it had happened between them had almost been an accident. Whatever the specifics of what was bothering him, it had to be bad for him to give Ironhide even that much indication of what he wanted. It honored the old warrior, and humbled him, that his Prime trusted him enough to share something like this with him.

"Optimus?" Ironhide asked softly, needing to be certain of Prime's intent. Prime shuttered his optics for a moment, and then met Ironhide's gaze with a level one of his own and a small nod.

"Please," he whispered, and Ironhide nodded in return. By unspoken agreement, they both got up and moved away from the edge of the cliff, neither willing to start this where anyone on approach to the Ark could look up and see them.

Once he judged them to be far enough back, Ironhide coaxed his leader to lie on his back on the ground and knelt over him. He ran careful hands across the red chassis and Optimus shivered, optics darkening in anticipation.

Ironhide felt his own anticipation flood him; interfacing with Prime was always a heady experience. He ruthlessly quashed a rising sense of inadequacy—Prime would not have continued to seek these occasional encounters if he did not enjoy Ironhide's touch.

Optimus suddenly reached for him, pulling him down flush against his chest and holding him tightly. Ironhide let him, keeping up his cautious caresses in an attempt to ease his beloved leader's trembling.

Finally Optimus began to reciprocate, rubbing his fingers along the crest of Ironhide's helm and across his cheek. The other hand he ran down Ironhide's side and then delved into a seam in the thick armor that he found there, making the old warrior murmur in pleasure.

Prime gave a sharp intake of air at the sound, tugging a little on the internal wiring to elicit more.

"It's not nice ta tease," Ironhide managed, whispering directly into his leader's audios, and Optimus laughed shakily.

"Serves you right, poking your nose into others' business," he replied, and Ironhide had no trouble hearing the smile in Prime's voice.

Ironhide snorted. "Ya like it when I pry in yer business," he said, trailing his lips across the battlemask and down Prime's jaw to nip at his neck. Optimus raised his chin obligingly, and the security officer made a soft noise of appreciation at having unobstructed access to the vulnerable metal there.

"Ironhide!" Optimus gasped, fingers tightening involuntarily in the wires they were tangled in and drawing an answering gasp from the red van. Their engines had rumbled to life, Prime's a deep throbbing note undercutting Ironhide's lighter tones.

"If I didn't know any better, Prime, I'd say ya liked that," the warrior chuckled once he felt he'd regained control of his vocalizer. He reached up to stroke one of the antennae that protruded from the blue helm; it was a move that Ironhide knew from experience could drive Optimus into overload if he kept it up long enough.

"Not fair," Optimus breathed, shuddering and leaning into the caress. His hands feverishly mapped out his partner's plating, seeking and finding every sensitive point that he could remember. He was rewarded with a drawn-out moan, and he winced when the security officer's hand clenched too tight around one antenna, but the pain was worth it to see Ironhide writhe against him like that.

"Now… who's not… playin' fair?" the red and grey mech panted, fingers already searching for an interface port to initiate the uplink. He was afraid that, if things kept up the way that they were, he wouldn't last too much longer. His cooling system was strained to its maximum, trying to keep his core temperature from exceeding his limits. Prime had to have been just as affected as he; Ironhide could hear his fans whirring away at top speed as well.

Optimus beat him to it; he snapped his link cable into place in Ironhide's interface port with a click that they both felt more than heard. Both mechs shuddered as the first flow of packets, all containing sensory information, began to trickle across the link, and they moaned outright when their systems finally came into synchrony. Suddenly every touch was magnified, echoing back and forth across their connection and gaining strength with each return volley.

Warnings began flashing across their visuals, indicating that their systems were approaching critical status; they paid them less mind than buzzing flies. They both knew very well what was happening, and didn't require redundant fail-safe software to tell them so. The part of Ironhide that was still coherent briefly wished he could turn the fragging things off.

The rest of him was too busy enjoying the way that Optimus Prime arched beneath him and called his name. He gave a choked cry when Optimus finally overloaded, triggering his own release as the excess energy generated was shunted into him across the link.

"Thank you," Optimus whispered once he felt that they had given themselves sufficient time to recover. He absently stroked the back of Ironhide's helm; the old warrior's cheek rested against Prime's chestplate.

Ironhide hummed softly in acknowledgement, too sated to manage anything more coherent. After a few moments of silence, he murmured lazily, "We really should do this more often," and pressed a kiss to one glass panel of Prime's windshield.

Optimus hesitated, and then replied, "I—would not wish to impose on you so, my old friend." His arms tightened fractionally around the red warrior, giving the lie to his statement.

Ironhide snorted, and somehow found the wherewithal to raise himself up on his elbows and glare at his Prime. "If you think this is an imposition, then yer glitched," he said firmly, and then lay back down before his arms gave out. He sighed. "I ain't exactly doin' this outta duty, Optimus, though there is that. I do it 'cause yer my friend, an' I know that ya get so strung out sometimes that ya gotta do somethin'—" Suddenly he paused, and then his tone became decidedly sly. "Not to mention, ya really know how to blow a mech's circuits," and he lifted himself up enough to grin shamelessly at his leader.

Optimus stared at Ironhide in consternation, expression somehow radiating embarrassed pleasure despite the mask that concealed the majority of his face. "You—" he began, shook his head, started again, "You're impossible," he said, optics filling with wonder. "You're really something else, did you know that?"

"O' course," Ironhide answered contentedly. "But ya feel better now, don't ya?"

Optimus laughed softly. "Yes—thanks to you." He disconnected the cable that still linked them, but Ironhide didn't need the physical connection to tell that Prime's outlook had lightened enough to allow him to continue on without faltering, at least for a time. Suddenly it didn't matter that it would likely be a long time before Prime needed him like this again. He was content in the knowledge that Optimus still had the strength and resolve to keep them fighting—and that Prime knew that, should he ever falter again, Ironhide would be there to catch him.