Loki has his Cosmology 101 class down to a routine by now. So much so, in fact, that he walks into the lecture hall, spreads out his notes and teaching aids, and takes his first drink of iced chocolate before he turns around and sees the giant in his audience.
He actually drops the mug. It's completely frozen by the time it hits the ground, so nothing is spilled, but still.
Unmistakably it is Thor, dressed in blue jeans and a high school letter jacket over a T-shirt. Perhaps he hoped to blend in, but the clothes only serve to make him stick out even more. It was ever so with Thor; Loki could blend into any environment by changing his clothes and his manner, but Thor somehow carried his own environment wherever he went.
And now, he is trying to make it Loki's classroom.
Thor is grinning at him from his seat in the first row, huge bulky form squashed comically into the tiny auditorium seats with their awkward half-desk armrest. The seats on either side of him are empty, not out of deference, but out of sheer logistics: each one of his arms practically takes up a whole chair by itself. He has the attention of the entire rest of the class, who are openly goggling and whispering to each other about this unexpected appearance of one of the Avengers in the middle of their lecture. Paying attention to Thor and not to Loki, their professor, because of course they are.
Loki's first impulse is to storm over there and throw Thor out, or at least demand an explanation for his presence; no doubt Thor expects this, if his shit-eating grin is any indication. And so Loki does no such thing; he acts as though Thor isn't even there, beginning his lecture in the usual manner. He does, however, append a direly worded warning that all of today's material will feature heavily in the exam; it is unspoken but clear that if they spend the period gossiping about Thor instead of taking notes, their grades will suffer for it. And it will be Thor's fault, not his.
Once the lecture is underway, Loki leaves a clone of his to teach the by-now memorized lesson and slips invisibly into the empty chair next to Thor's. "What are you doing here?" he hisses softly in Thor's ear, hoping for the satisfaction of making him jump. He doesn't get it.
Thor turns those big blue eyes on him, shining with innocence and sincerity. "I am expanding my education, Brother," he said piously.
Loki scowls at this obvious falsehood. Thor shouldn't do falsehoods; he's no good at it. "This is the history of the nine realms, Thor," he replies. "You should have learned all of this at your tutor's knee millennia ago!"
"Well, I am sure to get a good grade, then," Thor smirks, and Loki wants to smack him.
He settles for a direct and pointed jab in Thor's ribs, unpadded by the thin fabric of the jacket. Thor winces slightly. "We'll see about that," Loki growls. He has a good enough memory of Thor's childhood studies that he knows just where the weak spots are, oh yes.
"But in seriousness, Brother, I wished to see you teach," Thor continues, and the piousness is gone from his voice, replaced with something disturbingly like sincerity. "Professor Xavier was good enough to give me a day pass for the campus, and a copy of the students' dress code."
"I hope he also made it clear that students are not to interfere with a professor's lecture by an incorrigible need to show off," Loki snaps. He has no doubt that if Thor tried — or even if he half didn't try — he could make the entire ninety-minute lecture a presentation on The Greatness Of Thor.
"Of course not," Thor is quick to assure him. "For today, Brother, I am entirely under your authority."
Loki's eyebrows go up, and he smirks. "Really? And whatever possessed you to think that was a wise idea?"
"Clearly I still have much wisdom to learn," Thor says with a small laugh, "and so school is the perfect place for me!"
A moment later he sobers. "All jests aside, what else was I to do?" Thor says plaintively. "Since you made it so clear yesterday that your schedule was entirely taken up by teaching, and you would have no time to spend with me. Attending your lecture was the only way I could think of to see you at all."
Loki winces, feeling an unexpected twinge of guilt. He knows that Thor is only able to be here on Earth, here at Xavier's school, for a couple of days; it was nothing but cowardice to busy himself with schoolwork as an excuse to avoid seeing him.
"All right," he sighs. "After this lecture is over, I usually take a morning coffee break with Dr. McCoy over by the commissary. If you would care to, you could join us… Brother."
Thor beams at him like the sun rising, and Loki can't help but feel warmed by it as he rises from the awkward chair and returns to the podium to continue his lecture.