Resourcefulness
Competence
noun
The result (甲斐) of being your own gender shows your resourcefulness. Depending on your gender, certain things are harder than others, so your resourcefulness and competence will help you to overcome those hurdles.
かいしょう
This word combines the word 甲斐 (that you already learned) with the on'yomi reading for 性. You know them both, just put them together!
どうしてあの甲斐性無しが彼女の愛を復活させることができたのか、全く理解できないね。
I really can’t understand how such an incompetent man like that was able to rekindle her love.