Good for tanking bosses which are specifically female, as the defense buff is more effective but specific to only female enemies. Also keep in mind that Noble Phantasms with defense ignoration effects will not be affected by this CE.
Increase your DEF against [Male] by 25%
Increase your DEF against [Male] by 30%
How to use
What type of servants will equip the CEs? The best servants would be those that have a taunt as it allows the CE to have more effect on the battle.