Tennis no Ouji-sama: Atobe kara no Okurimono - Kimi ni Sasageru Tennis Prince Matsuri

Hyoutei Gakuen's strange (but impossibly wealthy) captain Atobe Keigo decides to throw a giant birthday party for his friend and teammate Kabaji. He invites the rest of the Prince of Tennis cast. Together they participate in many different sports and events: dancing, swimming, soccer, a relay race, and more.

(Source: ANN)