User blog comment:B214/Talk About What You Want! 2/@comment-108.27.243.235-20140707032420/@comment-1359322-20140707033107

None really? Well unless if the Harem consist of members of other clans, then it would serve to deepen the relationship between both clans. But if they aren't any of those, you can pretty much say there's no reward for having a harem except for personal interest.