When a turn rolls around during Flash Effect conditions (displayed on the left of the turn icon), certain effects will occur. The results range from HP Recovery to Damage Up. These effects happen not just to Verse Maidens, but MAD as well.
Because Flash Effects occur during turns, you can change the target of the effects by adjusting the Wait time and switching the turn order. For MAD, you can use Turn Delay to mess with the enemy's turn and prevent it from receiving a Flash Effect. You can also activate Live Concert Mode to remove the MAD's Flash Effect.