The Coming of Rei the Handsome Shapechanger! - Die Dreamy-Man!

Sinopsis

Shinobu meets upon Rei, Lum's handsome ex-fiancé, and brings him to Ataru’s house, much to the dismay of Lum. Ataru and his friends find Rei in a restaurant. His poor Japanese being mocked makes him go wild, and as he chases the boys and Lum throughout town, the chaos grows on.