Henry is one of Takato's best friends. Henry tries to make Takato stop using Guilmon to fight but he doesn't listen. He saved him most of the time in the start of the series.
Rika is cold towards Takato in the start of the series but that slowly changes as the show progresses. She starts to act less cold towards him, later becoming one of his best friends. He at one point dreams about her. In both versions Rika teases Takato that he has a crush on her. In the 2nd movie, it is shown that Takato cares very much about her.
Jeri is Takato's terminal crush. In many scenes of the show, Takato has shown his affections for her in many ways [Such as blushing when he gets very close to her]. In Message in the Packet, Jeri indicates that she also feels like Takato and that she thought he might invite her to a date rather than leaving an audiomessage. In the 2nd Audio Drama Digimon Tamers 2018: Days -Information and the Unordinary- they are engaged.
Ryo is Takato's idol. Takato has shown quite a lot of amazement towards Ryo [Such as being amazed at his being the card king].
Kazu is one of Takato's best friends from the start of the show. He would often beat Takato at the Digimon card game and gives him the nickname him "chumley" which shows they have a strong friendship.
Kenta is one of Takato's best friends as shown in the start of the show. He often would lose to Takato in the Digimon card game.
Suzie has hardly any relationship with Takato. She mostly only knows him as her brother's friend. She calls him the angry kid.
At the Digital Dungeon, Takato asks Tai to shake his hand and marvels at how cool it is.