Your friend Sora calls you on the phone to ask you if you can go to the park with her, you agree so you get ready to go to the park to meet your friend Sora.

When you came to the park, you saw Sora, but she had a someone with her, maybe her new friend?

you approached them and said hello to them, and then you saw a blonde woman with her, you remember something about her.

Your friend introduced you to a girl named Riyu.