Cologne was once Yuri's fairy partner in Heartcatch Pretty Cure!

During the events of Episode 1, he, along with Yuri, protected the Heart Tree until he died protecting Cure Moonlight from Dark Pretty Cure.

This left a scar on Yuri's heart as she tries to take revenge against Dark Cure. It's speculated that he gives Yuri her Pretty Cure Seed to transform into Cure Moonlight.

Cologne was very calm and caring for his partner.