User blog comment:Koishi-Komeiji/Mami Tomoe/@comment-38196594-20190817195234/@comment-24965192-20190817195647

10% passive Quick up equals to Riding at Rank A.

Thanks. I've changed the wording to make it easier to understand. The debuff she inflicts on the enemy nullifies their defensive class advantage fully for 3 turns. Note that the important word is debuff--so it affects the enemy. Anyone would be able to deal neutral damage (if not weak damage) to Rulers for those 3 turns.