BC Fill on Enemy Defeat

BC Fill on Enemy Defeat is an effect that boosts BB gauge of the unit by a certain amount upon defeating an enemy.
This effect does not activate when an enemy changes form as a result of reaching 0 HP. If multiple units utilize this effect, only the unit that deals the killing blow utilizes the effect.
==Examples==
*Two units are equipped with Demolishing Blade. Both of them attack the same enemy, defeating it. The unit that dealt the finishing blow will fill its BB gauge by 5 BC with the other unit not filling its BB gauge at all.