That Bod can’t see in the darkness of the ghoul-gate suggests that wherever he is now, the Freedom of the Graveyard doesn’t protect him. In this sense, Bod is totally alone, without anyone to care for him. This foray through the ghoul-gate, then, will test whether Bod is ready to tackle life on his own yet. His willingness to follow the ghouls implies he thinks he is, while his willingness to trust nefarious ghouls calls his maturity into question.