Atomweight by Emi Sasagawa

Good girl, good student, good daughter: Aki has always done what her loving but demanding multiracial family expects. Far from her Vancouver home, she adjusts to life in London­—studies, friends and a relationship with a wealthy but closeted Asian woman. Life is demanding, but Aki is coping until a violent incident triggers an unexpected response in the young Japanese-Latina woman. She discovers that brutal bar-fighting relieves her stress and she begins a dangerous dual existence—obedient and accommodating by day and brawling by night.
This is a novel about the need to reconcile competing cultures, traditions and values that also explores issues of sexual identity and violence. (From Tideater Press)