Simplify the following text for a Grade 9 native English-speaking person.
Original: Since 7 January 2007 , Gackt has been playing the warlord Uesugi Kenshin in the TV drama FÅ `` rinkazan Gackt 's most recent solo release is the single `` Returner ~ Yami no Shuuen ~ '' , released on June 20 , 2007 , which was the first in the artist 's career ( both solo and in a band ) to reach the number one spot on the Japanese Oricon charts . .
Simplified: Beginning January 7 , 2007 , Gackt played the warlord Uesugi Kenshin in the NHK drama FÅ `` rin Kazan . His single `` Returner ~ Yami no ShÅ `` en ~ '' , was released on June 20 , 2007 , and was the first in his career ( both solo and in a band ) to reach the number one spot on the Japanese Oricon charts .