Mysterious Girlfriend X (2012)

Season 1: Episode 7

After showing impressive display on the track, Mikoto is asked to participate in a relay race for the sports festival, although she rejects the idea of joining the track team as it means she wouldn't be able to walk home with Akira. As the students switch to their winter uniforms, Akira comes down with a cold. Having heard from Ayuko about how she dressed up in a bikini to help Kouhei get over a cold, Mikoto wears a bikini under her coat and gives Akira some of her drool, which helps him recover. On the day of the sports festival, Mikoto manages to help bring her team to victory in the relay race. Akira suggests to Mikoto that she should join the track team, but Mikoto once again rejects, as she much prefers spending time with Akira.