While staying with his cousin Genko, Harima is blackmailed into revealing his awkward past—including how he met Tenma and why he wears sunglasses. Little does he know, Tenma is sitting right behind him, hearing every word...

Hanai, smitten with Yakumo, volunteers his class to clean the school pool just to be near her. Chaos ensues as Tenma and the gang turn a simple cleaning session into an all-out aquatic battle.