Sheer Heart Attack, Part 8 (シアーハートアタック その⑧ Shiā Hāto Atakku Sono 8), originally Feeling of Defeat...!! (敗北感…!! Haiboku Kan...!!) in the WSJ release, is the three hundred sixty-first chapter of the JoJo's Bizarre Adventure manga. It is also the ninety-sixth chapter of Diamond Is Unbreakable.
Koichi stands before the serial killer, Yoshikage Kira. Repulsed that someone could perpetrate such horrible crimes, Koichi sends his Echoes at Kira, who summons Killer Queen. It effortlessly counters Echoes' punches and knocks it away. Koichi, confused that Kira could possess two Stands, is explained by the latter that Sheer Heart Attack is merely a sub-Stand. However Koichi doesn't have the time to think about it as Sheer Heart Attack is now out of Echoes' range and is no longer under its influence. Koichi is now obliged to defend himself against Killer Queen and Sheer Heart Attack at the same time, and chooses to attack the miniature tank first.
Killer Queen uses that opening to stomp Echoes on the ground, similarly immobilizing Koichi. Kira then proceeds to violently beat him up Koichi in retaliation for his earlier humiliation, among others slamming his head against the ground repeatedly. However Koichi declares Kira's name, having stolen his wallet while being beat up. Telling him that Kira was so careless as to let a helpless brat learn his identity, Koichi says that even if he dies, he will be waiting for him in the underworld. Humiliated once again, Kira has Killer Queen punch through Koichi in a fit of rage.