after future Gohan was killed, and trunks Time Machine was destroyed, he wanted to avenge Gohan. Android 17 quit destroying things and went to the other side of the planet. However, android 18 was still destroying things. They both fought, but android 18 was superior to him in strength, and beat him up. Trunks was on the floor with no energy left. android 18 picked him up by his collar and put him up to her feet, licking her lips

Android 18: tell you what, trunks. If you become my personal slave, I will not kill anyone else, or destroy anything. That being said, you will be my slave until your last breath. DEAL?