Kaichou-sama Ga Fiance DeKaichou-sama ga Fiancé de; 会長様がフィアンセで♥; 因为会长大人是未婚夫; Kaichou-sama ga Fiancee de

From Chibi Manga: A story about a friendly cool student council president and his popular vice president But the secret between these two is......they are fiancee