Tae-hoon caused an accident while trying to return goods to his friend Won-woo, whom he hadn't seen in a long time since being discharged from the military. After a few days of feeling guilty, Tae-hoon reunited with Won-woo who seemed like a completely different person, as he confessed to being an "intangible" version of Won-woo's other personality. Feeling responsible for the accident, Tae-hoon agreed to treat him as "Won-woo," but soon discovered that the intangible version of Won-woo was hiding a bigger secret...
