[@Jinxer]

sa·dism
ˈsāˌdizəm/Submit
noun
the tendency to derive pleasure, especially sexual gratification, from inflicting pain, suffering, or humiliation on others.
(in general use) deliberate cruelty.

scha·den·freu·de
ˈSHädənˌfroidə/Submit
noun
pleasure derived by someone from another person's misfortune.

I'd say it's just schadenfreude. She's not actually [i]inflicting[/i] the pain she's laughing at, so it's not sadism.

Also
[quote=@Jinxer]
P.S.  I have only recently discovered the meaning of schadenfreude relatively recently due to QI.  God Bless Stephen Fry.
[/quote]

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