Smiley approached Shuzo Hiragi at the behest of the Leo Corporation, who wished to have the champion Strong Ishijima Duel You Show Duel School student Yuya Sakaki, as Ishijima never got the oppurtunity to Duel the boy's father, who had no-showed at their championship match. Leo Corporation agreed to give You Show Duel School their new Solid Vision with mass system free of charge in exchange. Yuya eventually agreed. On the day of the Duel, Smiley functioned as a commentator.
After Ishijima lost to Yuya, he stepped down as champion and went overseas to train, leaving Smiley without a Duelist to manage. He eventually approached Yuya, offering a free entrance to the Junior Youth Championship if Yuya agreed to take him on as manager. Yuya refused, insisting he wanted to enter the tournament through the usual means. He instead asked Smiley to aide him in finding opponents to defeat, as he needed four more wins to qualify, to which Smiley agreed.
Smiley's first name comes from the onomatopoeia "nico nico", a term for when someone is all smiles.