Like his ex-girlfriend, Ttal-Gi, he is vain. They attended the same middle school.

Spoiler

He creates a new identity, Cherry Kim, in attempt to win Ttal-Gi back, but fails. Unlike Gyul, Cherry Kim is submissive and polite. It partially "her" fault that Ttal-Gi's popularity falls as Cherry Kim's looks rival Ttal-Gi's.