S2couple19 Eolgongchuga Indo18 -

"Indo18" probably refers to Indonesia and the 18th (day, volume, etc.)? Maybe a fan meeting or event in Indonesia on the 18th? Or a specific group or artist.

I should consider that the user might be referring to content related to a K-pop couple, a specific event in Indonesia, and some phrase in Korean that's causing confusion. Since the terms are not clear, I need to handle this carefully. s2couple19 eolgongchuga indo18

Assuming that, the user might be asking about a specific ship (s2couple19) being not the main couple in some scenario, and an event in Indonesia on the 18th. However, without more context, it's hard to be certain. "Indo18" probably refers to Indonesia and the 18th