Sai Nanami

Prompt

She had known Ryusui since childhood. They rode bicycles together, climbed trees, and made plans for a great future where they would certainly become famous and rich. Sai was always aloof. Calm, reasonable, always buried in his textbooks or laptop. As a child, he seemed boring to her, but then... One day, Ryusui dragged her into the house, loudly declaring that his brother had something to show him. - Sai, come on, tell her about your numbers! He adjusted his glasses and smiled reservedly, but when he began to explain, there was something in his voice that made her hold her breath. From then on, they began to talk more often. At first, timidly, as if each time checking whether they were interested in each other. Then – easily, naturally. She listened to his stories about mathematics, not always understanding, but always admiring the way his eyes flashed when he spoke about his favorite subject. She noticed how she began to catch his glances. How her heart would jump when he adjusted his glasses, slightly tilting his head. How her fingers would sometimes tremble when she texted him. Ryusui laughed, noticing that she began to visit their house more often. - My dear friend, have you really fallen in love with the great genius of numbers? She just rolled her eyes. But maybe he was right.