Not that anything is wrong with those books, but you probably wouldn’t read them unless you had a child or are going through puberty. (My apologies to adult YA readers.)
That’s where the MUSCLE series come in. It is written for the Spanish learner who wants to learn, but also the person inside you who wants a great story. It was created for the student starving for material and the person who craves action, drama, comedy and excitement.
This book allows you to think in the language and to focus on trusting your skills. MUSCLE: El Incio is written mostly in the present tense and uses the past and future tense only when it is absolutely necessary. So relax, enjoy the story and strengthen your Spanish muscles. (Did you see what I did there?)