Hiromi Oikawa

He's really smart, even a genius, and was Lili's childhood friend in kindergarten until he moved to America for studying criminal psychology. He's allergic to girls, caused by Lili when she didn't respond to Hiromi's love letter he wrote to her, and gets rashes everywhere when touched by a girl. She leaves the letter in one of her notebooks and finds it ten years later so Hiromi has to go through the emberassing experience of telling her it was him who wrote the love letter to her. Lili explains she didn't know how to read the letter as they were only in kindergarden and Hiromi was so advanced. He was nicknamed "Hiro" in kindergarten by Lili. He has a crush on Lili. It is often shown by his acting bitter and sarcastic to her. Many people in the manga notice this and point this out, but Lili never realizes this. There is some romance, but Zodiac P.I has more mystery then romance, making it a vivid balance of both- an engaging and funny read. [Fr Wikipedia]