Someone is very upset and making a scene. You have no sympathy. You think the whole situation is very entertaining. The sense of schadenfreude and shock at the improper outburst is strong enough that you can't help but make a face, but you are able to remain silent and you do so in order to remain as discreet as possible. You don't necessarily make eye contact with anyone else.
In the following picture, the girl on the right demonstrates this kind of reaction. The girl on the left might not be truly upset, but the depiction is close enough.
Is there a good word for this?