In episode 28, his role becomes more important. The Jetters are all sick due to the Bay Bay influenza, with the exception of Birdy and Gangu. With Shout extremely sick during an urgent matter, Rui takes her place temporarily. The Jetters head off to Swing Planet to protect the unique trumpet.
Rui also appears in the last few episodes. With Planet Jetters now heading to a collision course with Planet Bomber, Rui hung out at Jetters Base with Dr. Ein and the others. Rui would often point out what is happening.
Rui's relation with White Bomber is extreme. They share a very close bond with each other. White Bomber occasionally rides on Rui to deliver noodles to customers. When they're not working at the noodle shop, Rui watches White Bomber train.
White Bomber and Rui can be quite competitive when playing an actual game of Bomberman. In episode 32 Rui beats White Bomber, making White Bomber Rui's servant for a whole day.
Rui and Birdy's relation with each other is close. In episode 27, Birdy loses against Rui and White Bomber during a foot race. Birdy then gives the two a "Birdy do anything" ticket, which was used in succeeding episode where Birdy was ordered to eat Rui's noodles.
Rui and Shout's relation is close. Rui works in the noodle shop with Shout, helping out with the dishes and cooking noodles. Shout considers Rui better than White Bomber when working in the shop.