Shirayuki doesn't approve of Ikazuchi's morale boosting methods.
Nope, she's being largely ignored except as a convenient way to fill plot holes, which is becoming her role in the plot. I can totally see where Yuki-chan's coming from, here... I'd hazard a guess that Ikazuchi's only even hopping around with a whistle at all just because the artist felt an empty page with people staring was a cop-out, so he had a Kaminari Dance to fill space.
Furthermore, it looks like she's made of the same Flubber Inazuma's made of, she just has better control...
Updated
But I'd sink!OK, hold on.
Give me a moment...W... We should have Ikazuchi-chan put it all on her head when we swim back...?Yuki-chan's gradually becoming a bad person -nodesu.Take your time, -nanodesu.