As of January 2023, there are a million copies of the Bocchi the Rock manga in circulation. This number does not include digital copies and is for the entire series. So far there are five volumes, along with a comic anthology. Due to its success, there will be a second major reprint of all five volumes. [Thanks, Manga Mogura RE!]
There have been multiple reprints so far for the Bocchi the Rock manga, even prior to the second major one that will happen soon. The first three volumes have had around ten each, with Volume 1 at eighteen reprints. The comic anthology has had seven.
Bocchi the Rock, which runs in Manga Time Kirara Max, is not the first major success from the magazine. Other Kirara comics that have surpassed a million copies sold include Yuru Camp, Is the Order a Rabbit?, and K-On!.
— まんがタイムきらら編集部 (@mangatimekirara) January 20, 2023
Bocchi the Rock is a 4-koma manga series. Aki Hamaji both writes and illustrates it. It follows the story of Hitori Goto, who is an anxious and socially awkward girl who wishes to become a rock musician and make friends. She joins the Kessoku Band after Nijika Ijichi invites her to do so. The genre is comedy and slice of life, and the anime series for it ran from October to December 2022.
Bocchi the Rock will get a second major reprint in Japan. The anime is available on Crunchyroll.