"The Day Of Ants In The Sky" depicts the love story between a man and a woman who are both assassins for hire. Kenji (Kohei Kuroda) appears to be a normal college student, but he is also part of a covert assassination team. One day, while the team attempts to carry out a hit, a woman named Maki (Rei Orihara) enters the picture and kills the group's target. The woman also tries to kill Kenji, but Kenji's team takes her away.