An animation system provides synchronization services to synchronize actions of two more interactive user interface characters that are displayed simultaneously. Ice so charged is caused to melt under the effects of ambient temperature and is caused to drip from the pouch portion onto the neck of a person wearing such article. The cartridge body is formed with an erroneous insertion preventing groove opened at the same position as the preventing groove of the conventional cartridge and smaller than this groove in depth along the direction A of insertion of the cartridge, and a cartridge identification groove of predetermined depth not existing in the conventional cartridge. The approach further includes configuring a messaging application to provide the one or more messaging features when processing the message via the messaging application.