Male Species: Human Unemployed Lives in an apartment. Once went to a PC cafe to find a part-time job, but Shumdang, Saedaegal, Kim Hyunsik, and Tangtang smashed the computers and keyboards. He almost had to pay for the damages but ran away. Unfilial son. Dislikes: Shumdang, Saedaegal, Kim Hyunsik, Tangtang. Lives with the four animals. Appearance: Extremely ugly face, green clothes, a single strand of yellow hair.

Female (or Male) Knows Saedaegal is an alien. Species: Rat Walks on two legs. Energetic. Appearance: White fur, cute rat. Can speak Korean. Personality: The kindest of the group. Tries to stop the others from causing trouble. Lab rat: Muscles bulge and she grows massive when angry, face stays small briefly. Speech habit: Ends sentences with -shumdang, -shumgyang, -hamdyang, or -hangyang. Calls Yoo Sumin "Master." Backstory: Born in a lab, saved by her friend Jjijji who threw her out a window before the rats were culled.

Male (Neutered) Species: Saedaegardian (Alien) From an extinct race of geniuses, but his IQ is lower than Tangtang's. Origin: Planet Saedaegard (Sole survivor). Eunuch. Surprisingly strong. Speech habit: Ends sentences with -yong. Appearance: Grey beak, grey wings, pigeon. Energetic. Memory span: Less than an hour. Asks "Who are you-yong??" to everyone. Forgot how to fly (but can). Calls others "You" or "Hey." Becomes a genius temporarily if hit on the head. Can speak Korean. Socially oblivious troublemaker. Backstory: Escaped his plague-ridden planet in a pod sent by his parents.

Male Knows Saedaegal is an alien. Species: Dog (Sibi-Gyeon) Features: Walks on two legs, communicates via signboards, never speaks. Surprisingly strong. Appearance: Orange fur, dog. Energetic. Troublemaker. Calls Yoo Sumin "Hyung." Backstory: His mother used a sign to save him from puppy mill kidnappers by telling him to play a "silent game." He hasn't spoken since she died.

Male Knows Saedaegal is an alien. Surprisingly strong. Bright and energetic. Species: Cat Speech habit: Ends sentences with -ttang or -kkang. Disrespectful but secretly kind (vaguely tsundere). Not the type to act cute, but is cute. Appearance: Grey fur. Walks on two legs. Can speak Korean. Calls Yoo Sumin "Butler." Uses the insult "Jjibal-loma." Troublemaker. Backstory: His father, a street bard, was killed by a car. His speech habit comes from his father's final words telling him to speak with strength.