Falling Into My Bodyguard's Hug

When Helena's life is in danger, a man saves her life, it turns out that the man is the man who will work on her as a bodyguard, because of the incident of attempted murder that repeatedly happened to her. The man is Daiki, he is a serious and also mysterious man. Always with the man for 24 hours, will Helena not have the slightest thought on him? What about Daiki's actually mysterious life?