In "A Condition Called Love," Hotaru Hinase has gone most of her life without ever feeling romantic love. Still, she finds joy in everyday moments and time with those close to her, and she doesn't feel she needs a romantic connection. Love remains something she doesn't understand.
One day, while out with a friend, Hotaru sees her classmate Hananoi going through a painful breakup, even though they've never spoken before. Later, she spots him sitting in the snow and offers to share her umbrella. This simple gesture leads Hananoi to confess his feelings for her the next day. When Hotaru turns him down, he begs for a chance to prove himself, going so far as to change his hairstyle and retrieve her lost hairpin from the snow.
Even though she doesn't share his feelings, Hotaru thinks that dating him might help her learn what love really is. She agrees to his proposal and begins to experience being in a relationship, including learning how to respond to Hananoi's ongoing acts of kindness.