While chasing Roxas, Axel decides to make use of Kairi. He believes that since she knows Sora, she might be able to help him. He tries to make her come with him by silently threatening her with Dusks, but Pluto chimes in and the two escape through a dark portal. She ends up at Twilight Town, and Axel finds her once again. He literally drags her away. After some time, Axel meets up with Sora and apologizes for kidnapping Kairi. He probably realized that all he accomplished with that task was help out the Organization and make Sora's battle more difficult. All he wants is to see Roxas, but Kairi isn't the right person to make use of for that goal.