In order to maintain fairness among the family members, Regulars may form teams and get sponsored or supported by a family. There are side effects, the families will take advantage of the Regulars to meddle in their business. This is mostly because Rankers are prohibited to meddle with Regulars' business in the Regular's area.
If someone is born into a reputable family, he/she can directly receive a ton of support when climbing the Tower. It's very rare for an ace Regular to receive aid from other families, but in some special cases, ace Regulars may receive "personal aids" to climb the Tower.
Crew (크루, keulu, Crew) is a union of teams with many Sponsored Regulars.