One of the students who recently transferred to Eiden school. He is a good friend of Kazushi, Pierre, and Appo-. The four guys look up to Panchu as a big brother figure and deeply respects and fears Yagami.
Daigo is a gentle giant and very sensible. He is also very sensitive and rather romantic. The girls occasionally criticize him for looking older than he really is. Daigo also acts like an ape when he is nervous or excited.
During the school cleaning day, Rin requested the guys' help to get rid of all the caterpillars in the school field. Daigo explained that the caterpillars will turn into butterflies. She was surprised about the fact. Other girls in the class overheard Daigo and were impressed by his knowledge. Pierre then invited them to follow Daigo to the field to learn about nature.
When Appo- dismissed Hu-sen because she is no longer a virgin, Daigo punched some sense into Appo-. He explains that that fact meant nothing and that love transcends everything. Appo- realized the error of his ways and confessed his feelings to Hu-sen.
Later when Appo- and Hu-sen went on a date, the player can choose to spend the weekend with the guys. Daigo revealed a naughty magazine featuring a model who bears an uncanny resemblance to Mei. Pierre decided to produce a giant copy of the picture using the photocopy machine in the staff room. Mei walked in on them and kicked them out of the staff room.
When Appo- was caught helping Rei to run away, Daigo heard Sakura approaching them in the boys' dormitory even before the knocked on the door. Later when Haruka's doll met the guys, Daigo correctly guessed that she was a doll.
One day, Sakura wanted to see who had the biggest hand in the class. She compared her hand to Daigo's by touching him. Daigo was left speechless and he fell madly in love with Sakura. Daigo flew into a rage. The guys decided to lock him in the classroom to let him cool off. Rei walked in on him and he knocked her over. They fell in love there.
Later that night, he met with Rei at the school field. Daigo explained that he used to be small-sized during junior high and Kazushi protected him from bullies. He shared the same fate as Rei.