[Taking the lead with teasing is something she'll gladly do, since it's what she's doing half the time anyway.]

Really? He's heavy? That's hard to believe. [She looks back at Kaneki again as he makes his dumb joke. No way. He couldn't be that hard to carry.]

Oi. If that's the case, I have to see this for myself. I'll carry you instead. [This time she tries a joke with a serious face right back at him. Have a taste of your own medicine.]