Database: superhero
Question: Among the bad superheroes, what is the percentage of female superheroes?
SQL: SELECT CAST(COUNT(CASE WHEN T3.gender = 'Female' THEN T1.id ELSE NULL END) AS REAL) * 100 / COUNT(T1.id) FROM superhero AS T1 INNER JOIN alignment AS T2 ON T1.alignment_id = T2.id INNER JOIN gender AS T3 ON T1.gender_id = T3.id WHERE T2.alignment = 'Bad'