When it comes to Kokoro, essentially you should trust nothing she says
when she's dealing with Holmes and her group. She's created a devious
plan to get them all sick by putting them through numerous ordeals in
which they're exposed to cold things, from sno cones to large bags and
buckets of ice, in order to weaken them. All under the premise of doing
these ordeals will get them their Toys back. Being the gullible types
that they are, they embrace Kokoro's ideas wholesale and even come back
for more without questioning it at all. At least until they flat out
pass out from being sick with heavy fevers. Though they're in their
teens, their actions continue to paint them as tiny children who are
easily manipulated and abused.
Luckily for Sherlock and friends, Henrietta helps them out some by nursing them out of their colds since she feels sorry for such stupid people. In a way, you can't feel too sorry for them because of the way they've acted for so long and while Kokoro's friends aren't exactly all that keen on what she's doing, I found Kokoro to really be fun to watch as she takes the Holmes girls down a few pegs. I haven't cared for them too much from the start and seeing them abused is a bit of a guilty pleasure. The repeated abuse actually works out in Kokoro's favor at one point though as she stumbles into a room where they have Arsene spread out sick across a bed.