Joyful Summer (楽しい夏) is a brand found by Fumi Kazuyo. The muse for this brand is Hanami Vaquez. The theme of this brand is summer or happy motifs, sometimes having an edgy twist. It made it's cameo debut in Aikatsu! Next Melody episode 1 when it was seen on a giant screen in the city. It made it's official debut in Aikatsu! Next Melody episode 4 when Hanami was looking for a brand.
PS: Credit to Taka Shiba aka Ako-chan
Joyful Summer was made when Fumi went to America for vacation. Fumi loved how Summer could bring a smile to everyone's faces so she created Joyful Summer as a brand that could bring a smile to the wearer and to everyone watching the performance. This brand quickly gained popularity when it released it's first album of coords. The set was named Summer Lemonade, and offered unique coords that could bring a smile to anyone's face. Fumi never found a muse for this brand despite all the wearers as she wanted someone who made it shine especially. One day when Fumi was in the lake trying to find inspiration for her latest set of coords she met Hanami Vaquez. Fumi saw how brightly Hanami shone when she was having fun playing in the lake so she decided to make Hanami her muse as she thought that Hanami could make anyone smile. Together they released Summer Splash, a new album of coords made to make the wearer enter the stage with a splash and leave with a wave of smiles in the audience. The covergirl for this album was Hanami.