The conflict between Lola Pacini and Arlene Takahashi started sometime before (You Drive Me) Crazy in season 14 of Degrassi.

Conflict History

Season 14

In (You Drive Me) Crazy, Shay and Lola take a picture of Arlene and add rude text to the picture, then start giggling about it, which leads to Frankie reprimanding them for not being nice. In the end of the episode, they throw paper crumbles at her but Arlene doesn't seem to care. Shay asks Frankie to join them, but Frankie sits with Arlene instead.