My all-time favorite character would have to be Nanaka because she was so emotionally unstable throughout most of the episodes. It was just so surprising how she reacted when Sana didn't remember her. She was so pissed that she slapped him and gave him a bad look. When she finally let out all her feelings for Sana, it was a kind of embarrassing moment for Sana giving him a feeling of guilt. Wow, she held back a lot of her feelings. Very dramatic character.