Cowa! Ashcan (2008) by Viz Comics
Special Halloween Ashcan Preview of Cowa! Paifu - a half-vampire half-werekoala - is always getting into trouble with his best buddy, José the ghost. But when the Monster Flu sweeps through town, the fun and games are over. If the sick monsters don't get the medicine they need in a month, everyone will die! With all the adults sick, it's up to the boys to get the medicine and save the day!