This Figuretoon began as a simple picture of Sam and Mikaela laying on the hood of Bumblebee, mimicking this shot from the end of the first movie. Simple, straightforward, but lacking that certain "something" that would make it work as a Figuretoon.
Then we started thinking about how weird it is that the kids were dry-humping on top of a living, sentient being. It'd be like having sex on the back of a horse. A talking horse. That's kind of weird. To say nothing of the fact that all the other TFs are parked there at the time, looking on. It's like in medieval times, when courtiers would accompany the newlywed king and queen to the bed chambers to witness the marriage being consummated - the practice known as "bedding the bride," which gave its name to this toon.. That's when Ironhide and Optimus Prime joined the scene you see above.
Ironhide's line (and in fact, Optimus's line as well) comes from the second-season of Sealab 2021 - specifically the premiere. Bumblebee's thing may sound like a phonetic version of R2-D2's beeps and whistles, but Transfans immediately recognized it as the universal greeting. Meanwhile, Sam's denial was unplanned, but organic. If you've seen this video, you'll understand why.