Imagine they all had just passed around a joint.
Now Ritsu, just randomly, says SKULL
and Mio starts to shiver
And then Mugi says SKULL
and Mio starts to giggle
and then they're all laughing at Mio laughing.
And then Yui sends a text message to Azunyan saying SKULL and Azunyan is like, 'what the fuck?'
And Sawa-chan busts in and takes their ganja away because they can't handle it.