Kengo is a member of the Little Busters. He is skilled in the art of kendo and has a cynical personality, but his passion for the Little Busters is unmatched by anyone when he really opens up. He carries an air of honor and sophistication, complementing the physical prowess he evinces in being (self-allegedly) undefeated in 100 matches of kendo. On the other hand, he can be quite naive and childish. Just like the others, all he wants is to have fun. Still, he tends to wear a calm, mature facade, acting as a tsukkomi for the most part.
He supports Kyousuke's plan to strengthen Rin and Riki in the artificial world at first, however, he changes over time. He insists that Riki and Rin stay in the artificial world forever, and that he'll protect them. He doesn't believe they can ever grow strong enough to accept the fate that awaits them in the real world. He challenges Kyousuke's methods on many occasions and even physically attacks him during the baseball battle after the latter "bends the rules" to ensure victory.
In reality, Kengo just couldn't accept his supposed early death, especially since he spent so much of his youth practicing Kendo for his family's sake instead of playing even more with the Little Busters. He even pretends that his arm broke so he could spend more time with them in the artificial world. After being defeated by Riki and Rin during the second test in Refrain, he acknowledges their growth and his own weakness while in tears. He finally sees eye to eye with Kyousuke and the rest as his feelings are finally confronted.
During the initial bus accident, Kengo saved Rin's life by shielding her with his own body.
