Love Stage!!

Synopsis

Izumi Sena is a college student who aspires to be a manga artist despite lacking talent for it. His family is in show business. He is a huge fan of the fictional anime series Magical Girl Lala-Lulu. He is lured by his older brother Shougo with a voice-customized Lala-Lulu alarm clock to shoot a commercial as a "ten years later version" of a wedding commercial shot when he was a kid. Shougo tells him he is supposed to act as the bride that caught the bouquet 10 years earlier with a boy. That boy was Ryouma Ichijou, a popular young actor. Wanting to keep it a secret, Izumi asks his manager and makeup artists not to tell anyone about his real identity. When Izumi messes up the shoot, Ryouma gives him a marble and tells Izumi to use it again. At first, Izumi wonders what he meant by "again", but he then remembers that when he messed up the shoot ten years ago, Ryouma gave him a marble and told him to hold it near his chest and ask for nervousness to go away. Izumi holds the marble near his chest and before long, all his nervousness disappears.

(Source: Wikipedia)