Y/n groaned at the textbook in front of them. This was stupid. Why is biology so complicated? ‘It's the easiest of the sciences’ their science teacher had told the class. Bullscrap. There were just too many things to keep track of. The cells with all of their tiny parts with names longer than y/n's sticky notes allowed. 

Y/n glanced up at the old box TV, which was now displaying a variety of infomercials. They guessed show time was over. It was passed eleven now. They supposed that that made sense. 

They had tried to ask Raf for help, but as smart as he was with computers, he was clueless with organics. He had offered little more than a shrug, before going back to his own homework. Jack, you would think would know the most, being the son of a nurse and all. But he somehow didn't know anything about the unit they were taking. He was a grade above, and had dropped biology entirely as a course as soon as the school allowed. Apparently his memories of grade ten science were dropped as well. Then there was Miko, and, uh. Yeah, she wasn't much of an option in regards to help with class.

There was technically one more option, but y/n doubted that he would help them.

Besides, Ratchet was honestly a little scary. He meant well, but he was simply not tactful. When y/n had first met the autobots, and Optimus had introduced the idea of guardian's, they were honestly hoping for Bumblebee. He was nice to them on the drive to base. Anything, anyone would be better than the scary bot who threatened to step on the four humans, and yelled at them if they so looked at a machine the wrong way.

He had gotten easier to deal with as they came to understand each other, but there was always a slight spike of anxiety.

Y/n sighed at the worksheet. Perhaps a little too loud, because the only other person left in the base had noticed. 

“Do you not want me to drive you home? Or perhaps a groundbridge would be easier.” Ratchet rumbled from the monitors. He continued to type away as he spoke, the machines beeping before him with each interaction. “It is getting late. The others have already left.”

The implication was clear enough, ‘why are you still here?’ 

“I can't go home until I finish this stupid worksheet. The moment I get to my room I'm going straight to bed, and Mrs. Who Cares will kill me if I miss another homework assignment.”

That seemed to get Ratchets full attention, who perked up at the mention of said ‘homework.’ “Oh? Perhaps I can be of assistance.” He had turned away from the monitors completely now, and had that weird glint in his eyes he got with new projects.

“It's biology.” Y/n said flatly.

“I am a medic,” Ratchet retorted, “I am quite familiar with biology.”

“Sure, cybertronian biology, but this is organic matter. Tell me Ratchet, what is a flagella?”

Ratchet paused, running through the information in his mind. “It propels the movement of the cell. We have them too.”

“Oh.” y/n's expression shifted from embarrassment, to intrigue. “What, uh, else, do you have metal equivalents for?”

“I do not know. I do not know the human equivalents to compare to.”

Y/n held the work sheet up for Ratchet to see as he moved closer to the yellow couch that they were perched on.

“Hmm, yes. It would appear that our cells are made of similar structures. Although, cybertronians have an additional part to assist with mass displacement.”

“Mass what?”

“It is what allows us to compress into tight vehicle modes, such as Arcee transforming into a bike much smaller than her bipedal frame.”

“Ohh.” Y/n felt themselves warming up to Ratchet. He wasn't just lecturing them and being cruel, he was actually helping.

“Our cells are not circular like this diagram, they are more hexagonal…” Ratchet continued to point out the differences between organic and cybertronian life. “Hmm, cell decay is not of cybertronian concern, that is a uniquely organic issue… This is fascinating.”

Ratchet delicately flipped through the workbook with one finger. “I will fill in the responses to these questions on a data pad and turn it over to you to copy over.”

“I, what?” 

“I need to educate myself further on organic life, if we should be sharing a planet with it, it seems like a logical next step.” 

Y/n slowly handed the textbook over to Ratchet, who stored it in his chassis.

“But, I will only do this for you on one condition.”

Oh no, y/n should have seen this coming. He was probably going to make them scrub every inch of the base, or babysit Miko, or-

“Rest.”

“...huh?” 

“I will drive you to your residential dwelling now, and you will go recharge until morning. The grey underneath your optics suggest a need for a break.” 

Y/n touched the bags under their eyes, not realising that they had been that obvious. “Oh, okay…um, thank you.” Ratchet was actually being…nice?

“Don't get used to it,” Ratchet grumbled, “I am merely acting as your medic.”

Ratchet transformed, and y/n climbed down the stairs and up into the passenger seat.

The ride home was quiet, peaceful. Something told y/n that everything was going to be okay.