Tamako Harakawa (原川 玉子: Harakawa Tamako, also sometimes referred to as Auntie by members of the Detective Agency) is Haraken's aunt. As a consultant for Daikoku's Cyberspace Administration, she holds authority over the programming of Searchmaton and is responsible for its highly aggressive behavior. She is especially intent on preventing Yūko Amasawa from accomplishing her mission to summon a portal to Coil Domain. However Tamako herself is well-versed in hacking and the crafting of metatags, and she often oversteps her authority in investigating the protagonists' activities. Her fervent pursuit of making augmented reality a "safe place" stems from her re-opening the portal to the other side in her early days of hacking, thus initiating the constant battle between obsolete and new space.

She is also a former student of Megabaa, and caused an incident which ripped open a portal into Coil Domain, resulting in Megabaa losing memories of events immediately prior to the incident.

Her seiyu in the series is Junko Noda.