Although Chocolate Bomb is an earth pony, she becomes a Wonderbolt! Well, sort of. Not really. She does ground control work, which is a very important job, so she does contribute to the team in her own way. Her sister Cotton Tuft, who was already a Reserve by then, just had to introduce her to her chill new best friend, Sugar High. And as they both started working more closely together and learning the ropes of their work (even when it involved near-death experiences), they bonded together very quickly. Eventually, they even became a couple!  
Coco just loves when her girlfriend gives her sky rides. It’s a favorite bonding experience for both of them!