The Autobot washracks were cramped to the point of near claustrophobia, but the cleansing oils were warm and - more importantly - the room was empty. Optimus Prime stood relaxed and still under the showerhead, letting the oils disperse over his weary body, cutting through the grime of the day.
Unbidden, Optimus's hand found its way to his chestplate, tracing the sensitive seam beneath which his greatest weapon rested. Grimacing, he pulled it away. No. Have to stay focused. Resolute, he placed the treacherous hand upon the wall below the showerhead.
A low chuckle behind him made Optimus flinch. "Chief, we've really got to get you laid."
The Prime straightened hurriedly and turned to face his saboteur. "That won't be necessary, Jazz. I'm almost done," he added, apropos of nothing.
The look Jazz gave his commander was positively mournful. "Aww, harsh my fantasies, whydontcha." Optimus didn't dignify that with a response beyond a scandalized blink. He turned away, back to Jazz, and bent his head to let the cleansing spray get at his too-tense neck. Over the rush of cleansing oils he heard Jazz's approaching footsteps and tried not to react.
"Seriously, Prime." Jazz's voice had modulated again, low and gentle, with subtle reverberations that felt suspiciously like caresses against Optimus's armor. "This ain't healthy, what you're doing to yourself."
Burning with embarrassment, Optimus mumbled, "Don't you mean what I'm not doing to myself?"
"Whatever launches your shuttle." Though his tone remained just as gentle, Optimus could hear the smile in Jazz's voice. "I understand it's kinda scary if you're not used to it. I could help, y'know - you don't gotta do it all by yourself."
Optimus's internal workings hitched, cycled down to a lower torque. "That's... a very kind offer," he managed after a couple of false starts. "But I think I can manage."
"You sure?"
Somehow the concern in Jazz's voice deserved nothing less than total honesty. Optimus turned to face him, offering a smile of his own. "I think I have to do this myself."
Jazz chuckled. "All right. I'll make sure no one comes in."
"Thank you, Jazz." Optimus turned away again, and listened for Jazz's footsteps retreating. The door hummed shut behind the saboteur, and but for the showerhead, the washroom was silent again.
Internals still humming pleasantly with Jazz's kindness, Optimus let his hand drift down the center seam of his chest again. This time he didn't fight it when his fingers found the good spots, applying the exact amount of pressure to send him slowly and gratefully to his knees as the cleansers cascaded over his back.