Being the 3rd born child in his family, Henry has a little sister named Suzie Wong as well as an older brother and sister, Rinchei and Jaarin.
Henry is half-Chinese and half-Japanese; his father (Janyu) is Chinese and his mother (Mayumi) is Japanese. Along with his father, Henry is a Tai Chi student, a fighting style he would later use in combat when biomerged with Terriermon into MegaGargomon, when facing destruction at the hand of the Digimon Sovereign Zhuqiaomon. Henry meets Takato Matsuki at school and helps him after Guilmon gets into a bit of trouble.
Henry becomes a Digimon tamer after Terriermon passes out of the computer game and into his arms. After Henry realizes he has hurt many Digimon through the game, he promised Terriermon that he would never make him battle again. Henry is often reluctant to battle and refuses to allow Terriermon to absorb a Digimon's data. However, after many situations where Terriermon is forced to digivolve and fight, Henry realizes there are many battles worth fighting.
Henry is often seen as a protective older brother to Suzie and refuses to allow her to follow him even if he has to use force. He also jokes with Terriermon about his being one of Suzie's favorite toys, 'princess pretty-pants,' due to the fact that, for a long time, Henry hid Terriermon's existence from his family by having Terriermon pretend to be a stuffed animal. Henry also became good friends with Takato and Guilmon very quickly.
As a Tamer, Henry often thinks a lot about Terriermon and tries not to be reckless about slotting in his modify cards. When Henry couldn't get any data on the first Deva Takato and the gang encountered, he refused to give Gargomon any modify cards because he wasn't sure which ones to use. Henry helps Takato many times when Guilmon is in trouble and is often the most calm mind. In the season finale, Henry and Terriermon biomerge to become MegaGargomon and turns the D-Reaper into a harmless program, saving the world. When the kids return to the park, all the digimon start to glow. Sadly, Terriermon de-digivolves to Gummymon and his father explains that the Tamer digimon must return to the digital plain. Henry starts to cry and feels like nothing will ever be the same. Terriermon flies out of Henry's arms despite his protest and sadness along with the others.
Digimon Tamers: The Adventurer's BattleEdit
Henry and Terriermon went with Takato and Guilmon to Okinawa for summer vacation. Henry came to see the meteor which had landed near the islands and after returning to his hotel with pictures, he was phoned by his dad who told him that communication systems in Tokyo were going haywire before the phone went dead. Henry saw an Ebidramon attacking a ship and digivolved Terriermon to Gargomon to fight it. Afterwards, the two were warped with Rika Nonaka, Kyubimon and Omnimon to the VP Labs where Takato and Growlmon were fighting the true enemy: Mephistomon. Henry was present as the battle continued into an alternate dimension where Mephistomon became Gulfmon and WarGrowlmon, Rapidmon and Taomon created the "Trinity Burst" to defeat Gulfmon.
Henry returned to the Digital World with Rika, Takato, and Ryo to find and retrieve their partners. He is given a D-Nav in order to maintain contact with the human world. When Rika is captured by IceDevimon, he accompanies Takato to rescue her. He gets to observe, firsthand, Chaos in action when Takato melts a hole to gain access to his future girlfriend.
When Rika and Takato find a portal to the Digidestined's universe, Henry and Jeri follow after with their partners. During this time and later events, Henry began to develop a deeper relationship with Jeri.
Henry continues to serve as a voice of reason among the growing numbers of tamers and digimon (a necessary component to the team considering the increased number of hot-headed, impulsive goggle-heads).
Recently, when trapped in the past with Rey, Henry learned he is the Third Angel. Because he was not allowed to Awaken at his own pace, he has missed most of the important steps required and he fears that he may never truly be the Angel of Knowledge. Everyone from Ryder to Terriermon to Jeri has tried to reassure him, but he is still uneasy about his role and if he'll be able to fulfill it.