[5] A short story by Hernandez about the Sal and Gabi characters are featured in the anthology book, The Cursed Carnival and Other Calamities.

After his mother died, though, Sal developed the ability to reach into different dimensions, and he and his new friend, Gabi Real, have an adventure that spans multiple universes.

Gabi, a girl who Sal befriends over the course of the first book and grows closer to in the sequel, can be described as the optimistic student president of Culeco Academy.

Supporting characters include Gladis Machao, a girl who attends Culeco Academy with Sal and Gabi.

Aventura Rios is another girl who attends Culeco Academy, and Doctor Doctorpants is a silly teacher.

[7] After the second book, Sal and Gabi Fix the Universe, author Carlos Hernandez announced that he did not have plans to write a sequel.

At the same time, Sal is visited by an alternate version of Gabi called FixGabi whose universe was destroyed by the remembranation machine.