Airi Nogami (野上 愛理 Nogami Airi) is Ryotaro's elder sister and owner of the Milk Dipper that belonged to their parents. A motherly figure to her brother, she constantly tries to help Ryotaro in an attempt to find his lucky star. Originally, she was to be married to Yuto Sakurai on January 10, 2007, pregnant with their unborn child who is the Junction Point. However, Kai's intent to kill them to destroy the Junction Point forced Airi to allow Sakurai to erase himself and their child from normal time so they can evade Kai and his Imagin army. This resulted with Airi losing all memory of her fiancé Sakurai. Although she actually goes to the place she and Sakurai spent time together, the park at Kibōgahara after being hypnotized by Miura on accident, she cannot remember much, particularly about the railway watch which is all that Sakurai left.