Robotan is a robot made by a school boy named Kan-chan, a nerd. He has special abilities like "Robotan Copter", "Robotan Punch" etc. His arch Rival is Botchi, a small kid who dislikes Robotan and makes several plans to destroy him or make him a slave, but Robotan destroys all his plans. He has also a little crush on his teacher, Umi. He is very fond of bananas which gives him power. His male mentor Uminoyamais is also in love with Umi, at which Robotan is angered.