The short answer
Start Korean reach with Kakao Moment for targeting and a KakaoTalk Channel for relationships, and prepare Korean-language creative for approval.
Kakao is a major Korean digital ecosystem spanning messaging, content, and commerce touchpoints.
Kakao Moment is the primary self-serve advertising platform.
KakaoTalk Channel is the business communication tool equivalent to LINE Official Accounts in Japan.
Targeting leverages rich first-party data including demographics, interests, and purchase behavior.
Japanese brands should note that Kakao's ad approval process requires Korean-language creative.