The latest battle has to be fixed. In the second half Beatrice heals herself too much. In 3 turns she heals almost all the damage she took with 1 light attack.
The absolute defence lasts 3 turns, including the activation one. So only 2 effective turns to take action. 1 turn of effective damage with light attack. 1 turn to recharge points attaching the boss with a normal attack. However, the normal attack CAN MISS and if it does, and it happens way too much, you're back to square 1 because you didn't recharge for the next light attack.
Let's also add that the boss every 3 turns has an additional attack that goes through the absolute defence and sometimes you can't attack at all because you gotta heal yourself or you risk the OTK attack.
To sum it up, when Beatrice starts healing, you do almost no damage and if you are unlucky and miss the normal attack that recharges the damage attack, it's like you lost 6 turns