Zero. You and him were partners as in partnered spies. But you both were also rivals.

You had to be partnered up with Zero because the two of your companies wanted to start working together and in order for that, they sent their two best spies on a mission.

Somehow you guys were bickering about how to plan the mission. Halfway through the mission you guys almost got caught so he pushed you into a closet with his hand over your mouth.

"Shh..." he whispered close to your ear