Digimon Universe: Eri's Idol Training (Episode 21)

This is from working her way to be a top tier idol in order to be one of the Top 9 members of Appliyama 470 (the number 470 is the exact number of idols in the group). She was being trained by Coachmon despite the fact he was ordered by Mienumon, Leviathan's generals, wanted to kill her with Virusmon. Coachmon refused to do that and helped Eri to defeat the infected Weatherdramon, who got infected the L-Virus made by Virusmon. Her Digimon (Appmon) was Dokamon, an fighting-type Appmon, who can digvolve into Dosukomon and this episode AppFused with Coachmon into his Ultimate form, Oujamon.