I'll Set Things Right. Former Gangster Turned Lawyer Itsuki Touya

Wanting to help her aunt who is suffering through difficult times because of her abusive husband, Hanaori rushes into a law firm. There, she meets lawyer Sai, a super handsome guy with an undeniable yakuza vibe! He's usually sharp-tongued and hangs out with scary people, but in reality, he's a highly skilled lawyer with a strong sense of compassion who even conducts background checks for his clients! As Hanaori spends time with this unconventional but trustworthy man, she gradually finds herself drawn to him... Power harassment, sexual harassment, divorce issues... the reliable man, Higashiya Sai, will make sure you get your affairs settled!

(Source: Mecha Comic, translated)