Tobirama comes down to breakfast on the first day of classes to find the Great Hall full of snickering, his husband conspicuously absent, and his brother face-down in his eggs.

For an anon prompt on my Tumblr that I kind of hijacked: gai/obito tho, kakashi's utterly terrified of the two ever coming together. "I've met Gai, Kakashi, and guess what? I'm going /to befriend him/." "You wouldn't DARE, Obito." "Oh, I would. We're going to be best friends." Obito and Gai hit it off instantly, and it all goes downhill from there. Kakashi finds them making out once and it's so horrible. He's never going to get that image out of his mind.