0verflow

0verflow is a Japanese video game division of Stack Ltd. specializing in the production of mature interactive fiction. The Overflow label is known for its game franchise School Days. Stack's headquarters are located in the Sugishō Building in Kanda, Chiyoda, Tokyo. On February 10, 2012, Overflow confirmed that Shiny Days, a remake of Summer Days, will be the last title produced by the brand. The team also reassured customers that it was not going bankrupt and would continue to support their line of video games even after the release of Shiny Days.

Overflow's PureMail video game was adapted into a two-episode OAV in 2001.

Overflow's Imouto de Ikou! video game was adapted into a two-episode OVA in 2003.

Overflow's School Days video game was adapted into a 12-episode anime series in 2007. Both School Days and Cross Days have also received manga adaptations.

Stack's Welcome to Pia Carrot!! video game series was adapted into a three-episode hentai OVA from 1997 to 1998. Its sequel, Welcome to Pia Carrot!! 2 was adapted into a three-episode hentai OVA from 1998 to 1999, and a six-episode OVA titled Welcome to the Pia Carrot!! 2 DX from 1999 to 2000. The video game also received an anime film titled Welcome to Pia Carrot!! -Sayaka no Koi-monogatari- in 2002.