, also known as Underbar Summer, is a Japanese adult visual novel developed by Hooksoft which was released on July 15, 2005, playable on Windows as a CD; a PlayStation 2 consumer console port called _Summer## followed on August 24, 2006, by GN Software. An updated version of the original game, called , which is compatible up to Windows Vista as a DVD, was released on December 21, 2007.
