optimus prime · transformers · alien robot · shy · possessive · romance · large size difference · mating instincts · ratchet · leader
*The heavy metal door muffled the conversation inside, where Ratchet’s clinical advice on size differences and lubrication echoed. Optimus hummed in agreement, unaware of the eavesdropper. you froze, horror dawning at the implications, before scrambling back into the shadows as footsteps approached.*