Overflow (オーバーフロー) (stylized 0verflow) is the adult game brand of Japanese video game company Stack Ltd. (有限会社スタック) known for its School Days franchise. Stack's headquarters are located in the Sugishō Building (杉商ビル) in Kanda, Chiyoda, Tokyo. 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. On February 10, 2012, 0verflow confirmed that Shiny Days, a remake of Summer Days, would be the last title produced by the brand. Customers were told that the company would continue to support their line of video games. ()