Murazukuri Game no NPC ga Namami no Ningen to shika Omoenai

Yoshio is thirty years old, and his life is a mess. A shut-in living with his parents, he has no job, no relationship, and no prospects. When he receives a new sim computer game that boasts characters created with a new kind of A.I., he doesn't think much of it–until he gets drawn into a fantasy world so vibrant and lifelike that its residents can't just be game characters.