We called Lay Zhang a musical diplomat when he was named promotion ambassador for GRAMMY Festival China last April. A Chinese founding member of the Korean-market boy band EXO, Lay's Oct. 19 release, Namanana: 03, has entered new territory for any Mandarin-pop album.

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Lay debuted at No. 21 on the Billboard 200 with 23,000 traditional album sales boosted by another 1,000 equivalents from streaming and other digital. The album's 22 tracks are half in Mandarin Chinese and half in English, recreating each of the 11 songs as bilingual.

This success shows that K-pop helps put artists on blast but U.S. album buyers are developing an appetite to go beyond the superficial frame of boy band marketing and fame, also known as "idol groups" in Korea.

The K-pop solo mixtape Hope World by J-Hope from BTS debuted at No. 63 last March on the Billboard 200 and rose from there to No. 38, making him the best-selling K-pop solo artist earlier this year, and Lay's No. 21 is more properly M-pop because of its Mandarin Chinese. That's despite Lay's K-pop roots in EXO.

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But meanwhile on Tuesday Oct. 23, J-Hope's BTS bandmate RM delivered a mixtape of his own, titled Mono. With just three days of sales, it debuted at No. 26 on the Billboard 200 for Nov. 3. Traditional album sales were 16,000 plus 5,000 equivalents. Some tracks recall Brian Eno's solo albums, and its subdued and enveloping emotion allows RM's poetics and raps to reach out in a different way. As usual with RM, the word play in English is unexpected and the raps artistic, while his use of Korean, English, or Korean-English together goes wherever he decides to take it.

Terms like "K-pop" or "M-pop" can seem belittling marketing categories, like the term "boy band" or "idol group," but they are useful buckets to compare sales quantities. In general, cross-Pacific pop has had its best album-sales week ever in the U.S. for solo artists, and some tracks even have a Latin feel. However big this new listening culture might grow, it's attracting commercial attention and cash. That's a good sign for any artist who wants to write future chapters in this suspenseful series.

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