Juse (probably Juse Montoya in full) is a gang member of the Lobos introduced in the comic strip at the beginning of Witch Girls Adventures. He is friends with Juan and three other guys. He claims to be the older brother of Rosa Montoya.
What happens to him after this is not clear. He may have to avenge the deaths of hat Lobo (eaten as a cockroach) and possibly three others: Juse (who may have been left as a frog by Lucinda), blonde Lobo (last seen with a concussion, possibly dead from head trauma from Monica) and brunet Lobo (last seen being dragged underground by Lillian's skeletal army).