Adventures in the Digital World (デジタルワールドの冒険 Dejitaru Wārudo no Bouken?) is a novel series written by Takeru "T.K." Takaishi in Digimon Adventure 02. They are the in-fiction analogue of the Digimon Adventure and Digimon Adventure 02 anime, a chronicle of T.K.'s childhood adventures with the Digimon which presents the anime as a first-person account with T.K. as their narrator.
By 2028, T.K. has become a writer and tells his childhood adventures through novels. He is writing about Oikawa's sacrifice when his son calls him to meet with the other DigiDestined in the Digital World.