Miyuki is Dan and Coco's childhood friend and a Big Foot mechanic. She is a teenage girl with well-endowed body due to her huge breasts and wide hips.

Miyuki lived with Dan until her family moved away during their childhood. She and her grandfather returned in the first episode and now she is a beautiful teenager and a skilled mechanic. Upon her return, Miyuki teaches Dan how to pilot a Big Foot.

Miyuki cares for Dan and his team's Big Foots, something she does happily, as it gives her more work to do (and get paid for). Later, she redesigns the team's Big Foots, making them more flexible and agile than before, enough to create an afterimage.

Although not a Basquasher, she is still an irreplaceable part of the team, constantly fixing and upgrading all of their Big Foots. Miyuki has deep feelings for Dan, but she steps aside once Rouge comes into the picture, and accepts their mutual attraction.

(Source: Basquash Wiki)