“The reason Okabe kept trying — the one whose single "Tutturu☆" is worth saving the world for.”
The character who appears simplest but plays the most essential role — her existence is Okabe's moral compass. She isn't brilliant, but she reads emotions instinctively, and she holds Okabe together whenever he's about to collapse from within. She carries her own sadness inside and still keeps smiling, because she doesn't want to worry anyone.