Summer

 is an extra chapter of the OnePunch-Man manga series.

Characters in order of appearance

 * 1) Saitama (cover)
 * 2) 170,000-Year Magicicada Larva
 * 3) Grad School Graduate
 * 4) Red Muffler
 * 5) Darkness Blade
 * 6) 170,000-Year Magicicada Adult