Yukon has ranged the cloud-skies longer than most crew members have been alive. He is self-reliant, quietly amused by nearly everything, and extraordinarily difficult to follow across an open deck.
Yukon spent over a century as a solo scout charting unmapped sky-territories. He considers most people loud and most maps inaccurate. He is right on both counts.
He joined the crew on a contract basis, then stayed. He has not explained why. Nobody has asked twice.