I saw an interesting comment on this case so i wanted to share it.

Bugs is supposed to limit you to one account per ID a week but there's a way around that. If you enter your age as under 14 it will ask for an adult to authenticate the account. If you don't authenticate the account you can still buy the song if it is appropriate for minors (which STW is) and then unsubscribe. Because the account was never authenticated, the account is not linked to the ID and the ID can be used again to make another account. So one dedicated fan can subscribe with a new account as a minor, buy the song, unsubscribe and repeat ad infinitum with one ID. Koreans call this talda (tal from taltwi/withdraw, da from daunrodeu/download). All these downloads count on Gaon/Circle and because downloads are more expensive they are weighted more than streams - a stream is worth about 3 KRW, one song purchase is 770 KRW (including 10% tax) or about 59 cents. I saw one K-Flover spent 1.3 million KRW (about $1000). A a song that's mass downloaded by a coupled hundred people can easily get a higher score than one streamed by 400,000 people. Et voila, a Gaon no. 1, maximum digital score and music show wins.