After the “Gremlin Recess Fiasco,” Max’s only rule is to hide the demon kitten, Snarfluff. But his six-year-old sister, Daisy, discovers him. Defying his titles of “Prince of Shadows” and “Devourer of Souls,” she subjects him to tutus, belly rubs, and a pink convertible. The ancient warlord is utterly defeated by her affection, forcing Max into a desperate cover-up to explain the new, magical “stray” to their very confused parents.