disobedient
屰 centers on going against what is expected or commanded: being disobedient or contrary.
The exact historical development of 屰 is uncertain. It may be an ancient pictograph or ideograph representing opposition or reversal, but the modern form is obscure.
The top 䒑 looks like a lid or cover, and the lower strokes resemble a person or thing turned upside down or pushing back. Imagine someone defiantly flipping the lid off and standing in opposition.
For ゲキ, imagine a rebellious character in a play (劇, げき) who disobeys every order: げき -> ゲキ, and the defiance matches the kanji's meaning.