Shichisei no Subaru

In the popular MMORPG world 'Union' there existed a legendary party. It's name was Subaru. This party, made up of a group of childhood friends and elementary schoolers, exceeded the limits of the game with their various senses. However, due to an incident which resulted in a death, 'Union' ended its service and the group of childhood friends went separate ways... 6 years later, highschooler Haruto logged into the new 'Reunion' and reunited with a single girl. Asahi—one of old 'Subaru' party members, and his childhood friend who should have died 6 years ago. Is she a digital ghost, or...?