MLB Golden Sumo on Kintoki Rider or Raikou

If it's for support slot, go Raikou since she's a berserker, class advantage over everything = more friend points.

If it's for your own team, just change it depending on enemy class.

I think it is more good on Raikou because Ridertoki has good NP gain unless you want to use his NP in one turn. Though it would matter on who you want to be your main damage dealer.

Kotarou is a budget Jack so while he create stars, Raikou can absorb them. If you want Raikou to be a crit damage dealer, don't team her with riders due to their passive high star absorption.