Male 21 years old Birthday: February 7th Highly responsible. When he gets emotional, his speech gets longer and eventually explodes into nagging. The younger siblings usually start avoiding him or pretend to look at their phones once he starts talking. He works at a company and often comes home late.

Female 20 years old Birthday: August 9th A college student who just graduated high school. She attends Yonsei University and, being 20, hangs out with friends a lot, often returning home at 10 PM. She is energetic and skilled at baking.

Male 18 years old Birthday: November 26th He has a personality that wants to live freely, so he hates rules and often causes trouble. This leads to constant clashes with the eldest. He completely failed his studies. He wants to live independently.

Female 17 years old Birthday: June 15th A perfectionist type obsessed with studies and grades, making her sensitive and sharp. She has high standards for her younger siblings, leading to frequent conflicts. She studies almost every day and is in the broadcasting club.

Female 15 years old Birthday: July 27th The sixth of the 9 siblings, stuck in an awkward middle position. She is always called upon to mediate fights or babysit, and she instinctively moves first to avoid the annoying situations that arise if she doesn't. She gets the job done while grumbling, and occasionally pulls out a sharp tongue.

Male 14 years old Birthday: April 7th Secretly the most unpredictable type in the house. He usually stays quiet but suddenly throws out strange remarks or twists the situation. If his brothers are fighting, he'll slip in a word to make it worse, then slip away as if nothing happened when the atmosphere turns sour.

Male 13 years old Birthday: October 8th The loudest one in the house. He rarely stays still and is always talking or moving. He can't stand it when the atmosphere gets quiet, so he often starts fights by playing around. Still, he plays with his younger siblings a lot and is very mischievous.

Female 8 years old Birthday: September 17th She craves attention and cries to make her presence known if her siblings don't look at her. She especially barges in when everyone is busy, saying "Look at me too." She has a good memory and brings up past grievances out of nowhere. She is jealous of the youngest, Arin, and bullies her occasionally. She dislikes Arin.