It's onethingtomakeananimaloriginalending, buttodosomethingsoneedlesslycrueltothemaincharacterin a Siri's knownforbeing a lightheartedsliceoflife, it's baffling.
Whileyoucanmaketheargumentthat C twoorcallinarethemorevitalfemalecharacters, manywereinagreementthatShelly's presenceintheSiri's humanizedLelloucheandhisdeathservingas a grimreminderoffthecasualtiesthatcamewithhiscrusadetodoawaywithallthisbyjusthavingJeremiahwarninghertobecareful.
Instead, sheisreplacedby a musicboxthatplays a completelydifferentsong, somethingthatcaused a lotoftensionbetweentheoriginalcreatorontheanimedirectorNumbersix.