Why are there only 13 episodes in zombie loan?

"Zombie-Loan," an anime adaptation of the manga by Peach-Pit, consists of only 13 episodes primarily due to its limited source material and the pacing of the story. The series aired in 2007 and covered only a portion of the manga's plot, which may have contributed to the decision to end the adaptation early. Additionally, the show's reception and ratings may have influenced the production's choice not to continue beyond the initial run. This shorter format is not uncommon in anime, particularly for adaptations that do not achieve significant popularity or have sufficient material for a longer series.