Koi wa Etude!

Sora is a young actor who has had a great increase of popularity because of his charisma and acting talent. But Sora's true identity is a plain high school student, Rikuto Hoshino! One day, a classmate from the same school, Kakeru Kamizaka, sees through his disguise as Rikuto and recognizes him as Sora and, to make the boy shut his mouth, kisses him by force. Kakeru was innocent, contrary to Rikuto who was more than used to kissing for his work, which made him upset and confused. But it was that innocence that eventually caught Rikuto's attention.

(Source: Ichijinsha, translated)