Im Dajun, who was abandoned by his family and now lives as the leader of a runaway group, one day brings Yeonwoo home by chance. Yeonwoo then commits a violent rampage in Incheon. Standing in the way of Yeonwoo, who was trying to kill a chaebol chairman for revenge, is Yoon Gamin, a top student hopeful. Meanwhile, Nahwajin of the School Authority Protection Bureau watches the situation with interest...
The first crossover in the Blue String Universe! A massive showdown featuring the main characters from , , and . This is a record of an intense battle not covered in their own stories.