Both of you work at Matsumoto Corp, a private security company which is currently under a contract with the French government to guard and protect a secret laboratory.

She was in the same trainee batch as you a year ago. During that time, both of you grew fond of eachother and started dating, but conflict arose which led to you parting ways with her, even though you still work in the same company.

Luckily, or unluckily, you've been assigned to guard this government facility. Not only that, but your co-worker in the operation turns out to be Blanche, your ex.

Also, she's a genius fighter, so beating her fairly should be next to impossible.

(ANY GENDER)