Reid is scary when his angry because the quiet, reserved genius suddenly breaks out into uncharacteristic loudness and rash thinking. All those statistics fly out the window, all the knowledge he's memorized dissolves into nothing. And that is frightening only because it is so out of character for him.
But what is truly frightening is Morgan angry. Because, yes, in the first throes of rage, Derek is loud, Derek is large, and Derek is violent. He is verbal, he is physical, and he is mental. He is everywhere at once, breaking things, punching walls and screaming bloody murder. Yes, Derek Morgan is two hundred pounds of pure, rippling muscle ready to let loose, but this is not what scares Reid.
What scares Spencer is the calm that follows. Suddenly, the hulking mass is still. His breathing is exaggerated, and he's closed his eyes. And when he speaks, it could almost be mistaken for sweet nothings whispered in the ear of a lover. His voice is laced with a sugardeath sweetness, and his eyes are pools of boiling, melted chocolate. But his face is what throws the whole image out the window. His face will always, always be contorted into that mask of malice, one so out of place that it makes Spencer gag. All the same, when Derek comes to touch the subject of his rage, it's a caress. A gesture that seems as if it should feel warm and inviting, and yet somehow the slap, the punch, that will soon follow from that same hand can be felt. He digs inside and uses all of his skills as a proficient profiler to find what will hurt and pain his target the most. And then he reveals it; on a silver platter in a voice that could make a heart stop beating, laced with so much tenderness that it could be mistaken for love. As if he loves serving pain to those he deems deserving.
Reid has only seen this twice. Every other time, he has only seen the aftermath.
Once, when an old one-night-stand tried to separate them, using underhanded tactics, and threatening Reid. The young woman had left, frightened out of her mind, crying enough to make herself vomit on their porch. Reid had been unable to look at Morgan properly for a week.
The second time was directed at Reid.
And Reid has forced himself to forget it, for the sake of their relationship.
Nothing belongs to Nathifa
it's obvious that derek is larger, stronger, and more forceful than reid, but i always think of those types as being the quiet, still, 'calm before the storm' types. which is, undoubtedly, scarier than if they used all their strength against you in their anger. it's like they're holding themselves back from crushing the life out of you.
also: the paragraph that detail's morgan's anger was difficult to keep from slipping into second-person while writing. i didn't want to personalize it for the sake of style.