Sujimon Collection
After meeting the Sujimon Professor, Kasuga decides to collect the dangerous beings (Sujimon). First, he challenges Green, Red, and Blue. The Sujimon Encyclopedia is a convenient tool for checking information such as weaknesses and dropped items. Complete your collection of all 252 Sujimon and aim to become a Sujimon Master.
More info and screenshots here: https://gematsu.com/2019/12/yakuza-like-a-dragon-has-sujimon-collection-element