Wanna play dolls?
I can be Ken, and you can be the box I come in.
Wanna play dolls?
I can be Ken, and you can be the box I come in.
Alright, listen up, buttercup. The joke is that the person offering the pickup line wants their partner to be the box that the Ken doll comes in. The joke is implying that the listener isn't good enough to be the doll. You're probably the human equivalent of a participation trophy.