[Charlie listens carefully, nodding as Hange speaks, and then watches them pull a chair over to the vent.]

Oookay, I see what you're saying. [He doesn't.] That should work pretty well. [Will it? He has no clue.] Simple rectangular box. Yeah. [Seriously he's totally lost.]

So, uh, I'll just. Yup. [He scoops up the nails and a few hunks of wood and presents them to Hange. He's helping, right?] Where should we put the hand?