Zephyr Breeze

Zephyr Breeze is a male Pegasus pony and Fluttershy's younger brother who appears in the season six episode Flutter Brutter.

Development
Fluttershy's brother was initially revealed by Andrea Libman at the 2015 San Diego Comic-Con International.

In mid-March 2016, Jim Miller tweeted, "Spent the morning working on an #mlp6 episode with anew character I love to hate. Or is it hate to love?", and specified said character to be a "NEW character". On June 4, 2016—the day of Flutter Brutter's premiere—Miller tweeted, "15 minutes till you meet the character I love to hate! #MLPSeason6", and specified said character to be Zephyr Breeze.

Depiction in the series
Zephyr Breeze appears in the season six episode Flutter Brutter, introduced as Fluttershy's younger brother. He is depicted as a chronic slacker who freeloads off of his parents after dropping out of school.

When first introduced, Zephyr is stated to have pursued various interests before soon giving up on them, including mane therapy and sculpting. Unable to support himself, he frequently moves in and out of his parents' home in Cloudsdale, much to the frustration of his older sister. He is also heavily infatuated with Rainbow Dash, constantly flirting with her under the narcissistic belief that she is obsessed with him.

When Zephyr moves back in with his parents, his presence serves as a nuisance and burden to their way of life. He moves their knickknacks out of the way to make room for his own, and he re-purposes his father's cloud collection storage house as his art studio/meditation garden. When Fluttershy confronts him about this, her parents take her side, and Zephyr tearfully takes his leave—only to move in with Fluttershy soon afterward.

Though his presence in her cottage is just as cumbersome as before, Fluttershy allows Zephyr to stay on the condition that he get a job. However, his attempts at being employed usually involve him slacking off and getting others to do the work for him or otherwise quitting without even trying. As a result, Fluttershy kicks him out of her cottage, and he goes to live by himself in the Everfree Forest.

Incapable of living on his own, Zephyr eventually confesses to his sister that his unwillingness to try stems from a crippling fear of failure. Fluttershy convinces him that sometimes one has to do things, even if one might fail. With the support of Fluttershy and Rainbow Dash, Zephyr pursues mane therapy once again and graduates from mane therapy school.

Quotes
"Guess who's home! That's right, big sis, it's your one and only favorite little brother, moi."

- Flutter Brutter

"Sorry, sis, but when something's not the right fit, this pony's gotta fly!"

- Flutter Brutter

"Cracking the whip, huh? You always were kind of bossy."

- Flutter Brutter

"Turns out the animal communication thing isn't genetic."

- Flutter Brutter

"You don't have to come up with some excuse to hang out with me, Rainbows! Let's just go for a fly and see where the day takes us."

- Flutter Brutter

"What if I give everything I have and still fail? Honestly, I think it's better not to try at all."

- Flutter Brutter

"It was only a matter of time before they recognized my true genius! But actually doing the work probably helped."

- Flutter Brutter

"My parents are the best friends I could ask for!! Mom gives me all the space I need!!"

- My Little Pony Facebook post