Yokai Girls Vol. 5 (manga)
When Yatsuki and his friends hit the beach, their biggest worry is sunburn…until an aquatic yokai shows up and starts causing trouble! After the yokai snatches Rokka’s bikini top right off her, fun-in-the-sun turns into an underwater brawl! Yatsuki and Rokka have faced down some tough opponents in the past, but this time they might be in over their heads!