Side Story: My Best Friend Is a Girl!
"Wait a minute, Issei-kun/Shidou-san, you were a girl this entire time!?" Was the equally shocked reactions of the two reunited friends pointing at each other at the latter responder's home. See, Hyoudou Issei, former man, and now a female teenage high school student very elaborately hiding her current sex, didn't know that her old childhood best friend from long ago, Shidou Irina, was a girl this entire time.
Although to Shidou's credit, she had been somewhat expecting Issei to be surprised that she was a girl at first anyway. What she wasn't expecting when she walked into the Hyoudou household was to see that the charming young boy she had grown in love with in their short time together was a woman as well. Considering that she had him fooled by accident in the past... I believe the Buddhists would call this Karma, Shidou thought dryly.
Issei herself was surprised. Despite becoming used to the shift in her life since that fateful day almost 10 years ago, part of the reason she even went to the park that afternoon was to mourn the loss of her friendship. The fact that the boy she grew up and played with all those years was a girl this entire time had put an entirely new take on the interactions they had together growing up. The only reply she could muster at first was a bright red blush that covered her entire face.
"I um… yes. Yes, I was, Shidou," Issei said, pulling her cap down to cover her face. This was her best option if she didn't want to bring into attention the powers she now possessed, or how she got them. Although she only held a mild resemblance to her former face back then, age had simply made some to conclude that the boy from back then had matured in a different way.