Sarah's lucky that's Nanase on the ceiling right now.
Elliot, Ellen, or Diane would be yelling (though the first two would at least apologize for it. Diane would stand by it).
Grace, Tedd, or Justin would be freaking out.
Susan would just sigh, her silence beyond that deafening.
Ashley would be admonishing herself for not telling Sarah to watch out for the transformation spot. This might sound decent for Sarah, but it would be awkward as heck, not particularly helpful, and Sarah knows she messed up, and it would wind up being back and forth apologies.
And just for the heck of it, if it were Sarah up there and someone else stepped into that spot, she'd be somewhere between yelling and freaking out, and would lean towards one or the other depending on what the other person said.