He was Ken's partner during their adventure in the Digital World. After Ken was implanted with a Dark Spore, unaware of the consequences, Ryo took care of Ken before getting him back to the Real World.
Though Ryo holds nothing against Rika, their relationship is somewhat strained due to her pride, as she lost to him in the card game tournament. In the American dub of Digimon Tamers, Ryo tries to impress and even flirt with her, giving her nicknames like "Pumpkin" or "Wildcat".
Kazu is in awe of Ryo due to his status as the Digimon King. During the battle against ADR-06: Horn Striker, the two work together and Kazu's Guardromon even saves Justimon's life earning Kazu Ryo's thanks, causing him to be very happy.
Notes and references
|Main characters:||Takato Matsuki | Henry Wong | Rika Nonaka | Ryo Akiyama | Jeri Katou | Kazu Shioda | Kenta Kitagawa | Suzie Wong | Ai and Mako|
|Digimon:||Guilmon and Grani | Terriermon | Renamon | Cyberdramon | Leomon | Guardromon | MarineAngemon | Lopmon | Impmon and Behemoth | Calumon|
|Allies:||Omnimon | Mitsuo Yamaki | Monster Makers | Digimon Sovereigns | DigiGnomes | Alice McCoy and Dobermon | Minami Uehara and Seasarmon | Takehito Uehara|
|Villains:||Hypnos | Monster Makers | Deva | Mephistomon | D-Reaper | Locomon and Parasimon | Millenniummon|
|Relationships:||Takato Matsuki | Henry Wong | Rika Nonaka | Jeri Katou | Ryo Akiyama | Kazu Shioda | Kenta Kitagawa | Suzie Wong|
|Other media:||Battle of Adventurers | Runaway Locomon | Digimon Tamers 1984 | Message in the Packet | Brave Tamer | Digimon Medley | Digimon Battle Spirit / Ver. 1.5 | Digimon Rumble Arena | Digimon Adventure|
|See also:||Digimon | Digital World | D-Power | Digi-Modify | Digital field | List of episodes|