In this short book there are a handful of things to be aware of and discuss with your kiddo.
The biggest thing to know is that there are several mentions of ghosts or even a house being haunted. This is included due to people trying to explain the actions of Invisible Boy.
When Invisible Boy realizes an accident now allows him to turn invisible, before choosing to become a hero, the first thing he does is leave school (during school hours). He sneaks into a carnival, takes cotton candy without paying and even sneaks onto rides.
The book opens to a young boy lying to his mother about what he is doing (we do find out later this is the villain of the story). This boy has a soda even though not allowed (explaining it is a special occasion).
There are a couple slightly creepy drawings (short enough that you could flip through and see them easily to judge for yourself).
Upon seeing a really rundown cat, he thinks it is a zombie (he does comment he knows zombies are not real). There is also a mention of a werewolf (never feels dark).
The term “fart” is used as well as “foul stench of rotting flesh”. There are references to halloween.