Just a glimpse of your b-day gift, woman. :P
BIG. BAD. WARNINGS. FOR. STICKY-LIKE MECHSECKZ. NOT SAFE FOR WORK!
You've been warned.
He flinched, feeling the large piece of whatever it is that was sliding into his slick port become too big for his insides, forcing the pliable walls of his port to expand to accommodate the intruder. Moisture kept flowing through his insides, coating the invading object, making it easier for his lover to slide into him. He heard Prime release a long, lustful groan, and the arms around his middle held him a little tighter, bringing them close enough to exchange paint.
Starscream heard something click and before he could begin to wonder about it, he felt the spikes connect with the diminutive indentations within the walls of his port, sending a myriad of sensory input, then he felt the spikes scratch against the walls as they were dragged out of him. The spikes at the base and up to the middle retracted, but those from the middle to the top held in place, locking him and Prime together, and Starscream knew at this point, breaking free would be night impossible and extremely painful.
He did not think about that, however, hissing in a mixture of pleasure and slight pain as Prime thrust into him again, feeling the retracted spikes spring out again, connecting their tips to the indentations within his port.