Shinka is Yuta's classmate and class representative, who is also a cheerleader. One of the most popular girls in the class due to her looks, she is generally thought of a kind and gentle girl. The truth, however is that, much like Yūta, she was also a delusional teen who called herself Mori Summer and has also chosen a different high school from her previous classmates to escape her past. When she learns Sanae is in possession of the last evidence of her delusional phase, Shinka joins Rikka's school club in order to try and retrieve it. When out of the public eye, Shinka shows her true nature to be bit more bitter and easily irritable, particularly when dealing with Sanae. While Yūta initially admired her or even had a crush on her, after seeing her true colors, he is disillusioned and acts like friends with Shinka instead.