Kakkou no Iinazuke - Episode 12 - Hiro Stretches Arms

Hiro took Nagi to a kickboxing gym after studying at the library. That's a switch.

Hiro claims she took up kickboxing recently and wanted to share her hobby with Nagi. I think she just wanted to show off her body!

Erika saw Nagi and Hiro through the gym window and felt jealous. She took him on a date and made him work out with her. Erika couldn't articulate why she wanted his attention, but Nagi could tell. Nagi went home to his parents to clear his mind and found the love letters his dad had sent his mom in high school. Youhei doggedly pursued Namie-chan until she returned his feelings. Nagi then realized he had feelings for three women in his life: Sachi, Erika, and Hiro. It wasn't supposed to be like this!