Summary:

Drea Drea Serena Ver. (ドリドリ セレナver.) is the second version of the ending theme for the Pocket Monsters XY anime which was originally sung by Shoko Nakagawa. The Serena Ver. aired as the ending for a couple of episodes of XYZ and the song was also used as an insert song during that same episode. It replaced The Squishy Song for a couple of episodes as the ending.

The ending features Serena and her Pokémon preforming Tripokalon acts and dancing on stage.

News Article on official Pokémon XYZ Character Song Project website

The official Pokémon XYZ Character Song Project website announced on March 17th, 2016 that a new cover version of the song Drea Drea sung by Serena's voice actor Mayuki Makiguchi would air as an insert song and the ending during XY&Z 20 which airs on Thursday, March 24th, 2016. The original version of the song was sung by Pokénchi host Shoko Nakagawa and is available on CD.

Thursday March 24th, 2016 Broadcast of TV Tokyo series Pokémon XY&Z - "DreaDrea" Serena ver.

Next week, on the episode of the TV anime series Pocket Monsters XY&Z broadcast on the TV Tokyo Network Thursday March 24th, the final part of the Master Class Tripokalon will finally take place!!

Will Serena become Kalos Queen!?
Since they're airing a Serena-centric Tripokalon, they're going to use a Serena version of "DreaDrea" as an insert song!! And!! As a special treat, the ending theme this day is also going to be the "DreaDrea (by Serena as voiced by Mayuki Makiguchi)" version!! And there's even more!!

The day this episode premieres, ringtone and anime size single-track digital download versions of "DreaDrea (by Serena as voiced by Mayuki Makiguchi)" will be available from Thursday March 24th!! Definitely look forward to it!

Source: http://www.pokemon-xyz-charactersongproject.com/news/archive.html?465785

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