Di Gi Charat Fantasy Excellent

A boy with a long-standing crush on Dejiko is swept through a dimensional vortex alongside Dejiko, Puchiko, and Rabi-en-Rose into a fantasy world. He and Dejiko are separated from the others and find themselves alone in a forest — and Dejiko's memory is gone. The amnesia strips away her usual abrasive confidence, leaving her quiet, innocent, and shy: a very different Dejiko from the one anyone familiar with her would expect.