"Hey, Mako?"

His arms fall to his side as he lets the fire extinguish, turning at the sound of his younger brother's voice.

Bolin strides into the training room, plunking down on a pile of earth disks to strip off his boots.

Mako begins to practice the drills again, ignoring the sheen of sweat glossing his forehead.

"What does it mean when a girl wants you to go down on her?"

The fire plumes outward, billowing uncontrollably before Mako stops the drills, coughing weakly as his breath catches in his throat. His brother's innocent face peers at him.

"Are you all right?"

"Fine," he replies, bending over as more coughs wrack his body, fighting a blush.

"So what does it mean?"

"Um… you see, when a girl…" he stutters, unable to muster up enough breath between laughing and weakly coughing to explain.

"I mean, I figured it meant she wanted to go down to the carnival or something on a date, so I invited her over later tonight."

Mako's laughing becomes an all-out guffawing as his hands lower to his stomach to stop the pain spreading from his laughter as he slides to sit on the floor.

"Mako?" his hands wave in front of his brother's face, and Mako tries to compose himself, ignoring a stray snort that escapes.

"Oh, Bolin…"

"Can you explain?" he asks, sitting next to Mako, eyes wide.

"Alright. You're fifteen; I guess it's time for this talk."

"This talk?" his button nose wrinkles as he furrows his eyebrows.

"So… when a boy likes a girl, they do stuff."

"Do stuff? I mean, I like a lot of girls."

Mako resists the urge to smack his own face with his hand, and looks away from his younger brother, in disbelief that he has to give this speech. He almost tells Bolin to ask Toza, but no doubt Toza's speech would be tenfold more interesting.

"Yeah. I mean, when a girl and a guy have an attraction and have known each other for a while - or sometimes not at all… what I mean is that sometimes a guy and a girl… if there's a surface…"

Bolin laughs at his brother's attempt, shaking his head. "What are you talking about?"

"After you've been kissing a girl for a while, sometimes you… you take off your clothes and…"

"Why would you do that?"

Mako hangs his head in his hands, cheeks flaming even more.

"Well, you know how girls have boobs-"

Bolin snorts. "Of course I do."

Mako ignores the comment, moving on. "Well, girls have something else, except… like…between their legs… I mean, that we don't have."

"Oh…kay…"

Mako ducks his head again, unable to look anywhere but absently at inanimate objects.

"And when you kiss for a while… stuff happens."

"You keep saying 'stuff.'"

"Stuff! Like sex! You jam your bodies together until you're both happy enough to not talk for a while, okay?"

Bolin looks taken aback, and leans back slightly.

"So… is that going down?"

Mako's head makes contact with his hand, and he sighs.

"That's… you do that except with your mouth."

"So just a more efficient way of not talking for a while?"

"No… girls just complain and want more."

"More of what? Why do they want it, then?"

"Because they like it! And girls can do it too, but it's not called-"

"Wait. So you kiss a girl and then take off your clothes and rub your bodies together and then she shuts up for a while?"

"Sure, Bolin."

Bolin shrugs, standing to punch toward an earth disk, which flies into the wall.

"Sounds good. She'll be here soon. She talked too much anyway."