Loser King

A great racer who is known and revered as “The Legend” (伝説様, "Densetsu-sama"). He went missing 100 years ago, leaving behind a number of records that nobody's been able to beat. A huge black star is carved on its back, as if to show off to those who challenge him.
~!He's implied to have ties to Tomoe, possibly being her previous partner before Shiro.!~

(Sources: Official Website, JP Wikipedia, edited)